THE 19TH AUSTRALASIAN PLANT PATHOLOGY CONFERENCE

25-28 November 2013 Owen G Glenn Building University of Auckland Auckland, New Zealand

THE 19TH AUSTRALASIAN PLANT PATHOLOGY CONFERENCE ABSTRACT AND PROGRAMME BOOK

Gold Sponsor

Gold Sponsor

Bronze Sponsor

Thank you to our conference sponsors Gold Sponsor Student Presentation Sponsor Student Poster Sponsor

Gold Sponsor

Bronze Sponsor

Keynote Sponsor

Ross Beaver Memorial Sponsor

Workshop Sponsor

Lanyard Sponsor

Conference Sponsor

Exhibitor

Exhibitor

Exhibitor

Satchel Insert

WWW.APPS2013.CO.NZ

Welcome On behalf of the North Island branch of the Australasian Plant Pathology Society and the Conference organising committee, I would like to welcome you to the 19th Biennial Australasian Plant Pathology Conference. We have made a concerted effort to put together an exciting programme on “protecting our crops and native flora”, with excellent keynote speakers, offered papers and posters. Our eight themes are designed to cover every aspect of plant pathology, and to include talks and posters from nematologists, mycologists, bacteriologists and virologists so that we can learn from progress made in each other’s sub-disciplines. We thank the members of our society who are organizing eight workshops, including two field studies, to further facilitate interaction and learning. We trust you enjoy the City of Sails, Auckland, and get a chance to experience this first hand after the conference on the numerous cruises, charter yachts and ferries that criss-cross the Waitemata Harbour, as well as other sources of scenic beauty in Auckland and throughout New Zealand. Kerry Everett APPS 2013 Conference Convenor

Contents Welcome.........................................................................................................................................3 The 19th Australasian Plant Pathology Conference........................................................................5 Social Programme..........................................................................................................................9 The McAlpine Lecture..................................................................................................................10 McAlpine Lecturer 2013...............................................................................................................11 Allen Kerr Postgraduate Prize......................................................................................................11 Keynote Speakers........................................................................................................................12 Programme...................................................................................................................................21 Oral Presentation Abstracts ........................................................................................................33 Poster Abstracts.........................................................................................................................105 Presenter Index..........................................................................................................................181 Author Index...............................................................................................................................184

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THE 19TH AUSTRALASIAN PLANT PATHOLOGY CONFERENCE | Auckland, New Zealand

The 19th Australasian Plant Pathology Conference Plant & Food Research and the APPS are proud to present the 19th Australasian Plant Pathology Conference

Venue The University of Auckland Owen G Glenn Building Level 0 (level below ground level) 12 Grafton Road Auckland

Level 0 Owen G Glenn Building Level 1: Entrance from Grafton Rd Level 0:

Registration

k ar r P ors Ca vat e El

Rest rooms

Case Room 4

Case Room 3

Case Room 1

Case Room 2

Central Elevators

Lecture Theatre OGGB 4 Stairs to Level 1


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Sponsor’s profiles Gold Sponsor CRC Plant Biosecurity The Plant Biosecurity Cooperative Research Centre (PBCRC) was established in recognition of the need to strengthen the plant biosecurity scientific capacity of Australia. The PBCRC aims to develop and deploy scientific knowledge, tools, resources and capacity to safeguard Australia, its plant industries and regional communities from the economic, environmental and social consequences of damaging invasive plant pests and diseases. Through 27 participant organisations, the PBCRC coordinates plant biosecurity scientific research across the country and internationally through its international participants, providing linkages, participation, resources and science.

Gold Sponsor Grains Research & Development Corporation The Grains Research and Development Corporation (GRDC) is one of the world’s leading grains research organisations, responsible for planning, investing in and overseeing research, development and extension to deliver improvements in production, sustainability and profitability across the Australian grains industry. The GRDC’s primary objective is to drive the discovery, development and delivery of world-class innovation to benefit growers and the wider community. In consultation with industry, Regional Panels and Regional Cropping Solutions Networks, The GRDC invests over $150 million a year in RD&E activities to deliver productivity and profitability gains to Australian grain growers.

Bronze Sponsor SCION Scion is a Crown Research Institute (CRI) specialising in research, science and technology development for the forestry, wood product, wood-derived materials, and other biomaterial sectors. We are New Zealand’s leading CRI in forest biosecurity and risk management. Our pathology group specialises in diseases that affect New Zealand’s trees. We offer capabilities to support the health of all forest types: planted, conservation and urban forests. Our capabilities include: • • • • •

Biosecurity, surveillance and diagnostics Chemical control of forest pathogens Biological control using fungi and viruses Site manipulation to reduce disease Inducing resistance and improving growth in trees through micro-organisms or genetic selection

www.scionresearch.com

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Sponsor’s profiles Exhibitor Australasian Plant Pathology Society The Australasian Plant Pathology Society is dedicated to the advancement and dissemination of knowledge of plant pathology and its practice in Australasia. Australasia is interpreted in the broadest sense to include not only Australia, New Zealand and Papua New Guinea, but also the Indian, Pacific and Asian regions. Although the Society’s activities are mainly focused on the Australasian region, many of the activities of our members are of international importance and significance. Each member of APPS is an associate member of the International Society for Plant Pathology. Through the International Society, APPS is a member of the International Union of Biological Sciences (IUBS), the International Union of Microbiological Societies (IUMS), in liaison with the UN Food and Agriculture Organization (FAO), and the International Council for Science (ICSU).

Exhibitor Conviron Headquartered in Canada and with a global sales, distribution, and service network – Conviron is the world leader in the design, manufacture and installation of controlled environment systems for plant science research. Conviron controlled environments provide precise, uniform, and repeatable control of temperature, light, humidity, dehumidification, CO2, and other environmental conditions. All environmental parameters can be remotely programmed, monitored and analyzed with unparalleled accuracy and convenience. From small reach-in chambers, to large walk-in rooms, the Conviron Growth House™, the Conviron Research Greenhouse, and customized designs Conviron controlled environments can be found in small start-up facilities to many of the world’s largest and most prestigious universities and research facilities in over 90 countries. Learn more at www.conviron.com or contact us at [email protected]


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Organising Committee Local organising and scientific committee: Kerry Everett Chair, Plant & Food Research Bénédicte Lebas Ministry for Primary Industries Mike Pearson The University of Auckland Nick Waipara Auckland Council Peter Johnston Landcare Research Robin MacDiarmid Plant and Food Research Yvonne McDiarmid Plant & Food Research

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PLANT DORMANCY SYMPOSIUM 2013 | Auckland, New Zealand

Social Programme Welcome Reception

Monday 25th November | 6m – 7.30pm The evening reception will be held at the University’s Fale Pasifika, the spiritual home of the University’s Pacific community. Follow signs from the Registration Desk. Venue: The University of Auckland Fale Pasifika Wynard Street Auckland

Wine & Cheese Poster Session

Tuesday 26th November | 6pm - 7pm

Rugby Club BBQ

Tuesday 26th November | 7pm - 10.30pm This is an opportunity to mix and mingle at a traditional “kiwi BBQ” at the Teachers Eastern Rugby Football Club, once the rugby home of Andy Dalton (All Black’s Captain 1982-85). Buses will depart from outside of Owen Glen at 7pm sharp. Venue: Teachers Eastern Rugby Football Club Reihana Stret Tamaki Auckland

Gala Dinner

Wednesday 27th November | 7pm - 12pm The conference dinner to be held in the Squadron Ballroom and Dinghy Locker, at the Royal New Zealand Yacht Squadron. Buses will depart from outside of Owen Glen at 7pm sharp. Venue: Royal New Zealand Yacht Squadron Westhaven Drive Auckland


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The McAlpine Lecture The invitation to present the McAlpine lecture to the biennial conference of the Australasian Plant Pathology Society is extended to an eminent scientist in recognition of their significant contribution to Australasian plant pathology. The lecture is named after Daniel McAlpine, considered to be the father of plant pathology in the Australasian region. His most notable contributions were to study wheat rust following the 1889 epidemic, to classify and describe Australian smuts, and to recognise Ophiobolus graminis (now Gaeumannomyces graminis) as the cause of wheat take-all. He also collaborated with Farrer on resistance to rust in wheat (John Randles 1984, Stanislais Fish 1976). In 2013, the McAlpine Lecture will be delivered by Dr Shaun Pennycook from Landcare Research, New Zealand. PREVIOUS MCALPINE LECTURERS 1976

Dr Lilian Fraser, Department of Agriculture, NSW Disease of citrus trees in Australia- the first hundred years

1978

Dr David Griffin, Australian National University, ACT Looking ahead

1980

Mr John Walker, Department of Agriculture, NSW Taxonomy, specimens and plant disease

1982

Professor Richard Matthews, The University of Auckland, NZ Relationships between plant pathology and molecular biology

1984

Professor Bob McIntosh, University of Sydney, NSW, and Dr Colin Wellings, Department of Agriculture, NSW Wheat rust resistance: the continuing challenge

1986

Dr Allen Kerr, Waite Agricultural Research Institute, SA Agrobacterium: pathogen, genetic engineer and biological control agent

1989

Dr Albert Roveria, CSIRO Division of Soils, SA Ecology, epidemiology and control of take-all, rhizotomies bare patch and cereal cyst nematode in wheat

1991

Mr John Walker, Department of Agriculture, NSW Plants, diseases and pathologists in Australasia- a personal view

1993

Dr John Randles, University of Adelaide, SA Plant viruses, viroids and virologists of Australasia

1995

Dr Ron Close, Lincoln University, NZ The ever changing challenges of plant pathology

1997

Professor John Irwin, CRC Tropical Plant Pathology, Qld Biology and management of Phytophthora spp. attacking field crops in Australia

1999

Dr Dorothy Shaw, Department of Primary Industries, Qld Biology and management of Phytophthora spp. attacking field crops in Australia

2001

Dr Alan Dube, South Australian Research and Developmnet Institute, SA Long-term careers in plant pathology

2003

Dr Mike Wingfield, University of Pretoria, South Africa Increasing threat of disease to exotic plantation forests in the southern hemisphere

2005

Dr Gretna Weste, University of Melbourne, Vic A long and varied fungal foray

2007

Dr Graham Stirling, Biological Crop Protection, Qld The impact of farming systems on soil biology and soil-borne diseases: examples from the Australian sugar and vegetable industries, the case for better integration of sugarcane and vegetable production and implications for future research

2009

Assoc. Prof. Phil Keane, La Trobe University, Vic Lessons from the tropics- the unfolding mystery of vascular-streak dieback of cocoa, the importance of genetic diversity, horizontal resistance, and the plight of farmers

2011

Honorary Professor Lester Burgess, University of Sydney, NSW A love affair with Fusarium

2013 Dr Shaun Pennycook, Landcare Research, NZ Fungal Names in Flux

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McAlpine Lecturer 2013 Shaun Pennycook Shaun began his working life with 10 years on high country sheep stations in the South Island mountains, before enrolling for a BSc in Botany at the University of Auckland. He was recruited by DSIR Plant Diseases Division (PDD), and in 1974 completed his PhD on the phylloplane microflora of unsprayed apple trees. During his years as a PDD plant pathologist, Shaun specialised in diseases of fruit crops. He made significant pioneering studies of the emerging diseases of kiwifruit, including a taxonomic study of Botryosphaeria pathogens, which clarified species differences and described two new species. His work on botrytis storage-rot of kiwifruit formed the basis for recommendations that reduced disease incidence without using chemicals, so that post-harvest botrytis rots are no longer a commercially significant problem for the New Zealand industry. One of his major legacies was the 1989 publication of a three volume book, “Plant diseases recorded in New Zealand”, a valued resource for New Zealand plant pathologists to this day. Subsequently, as a mycologist at Landcare Research, Shaun focussed on fungal nomenclature and taxonomy, rather than phytopathology, but continued to contribute to the electronic databasing of plant disease records. He “retired” in 2009, but remains active as a Research Associate at Landcare Research; as Nomenclature Editor of Mycotaxon (the International Journal of Fungal Taxonomy & Nomenclature); and as a member of the IAPT Nomenclature Committee for Fungi and the Sub-committee on Governance of the Code with Respect to Fungi.

Allen Kerr Postgraduate Prize The Allen Kerr Postgraduate Prize commemorates the significant contribution to research in plant pathology made by Professor Allen Kerr AO, recipient of the inaugural Australia Prize. The award is made at the APPS biennial conference and is open to postgraduate student members of APPS undertaking original research relevant to Australasia. The prize is awarded by the Society for the best piece of original research by a postgraduate student in the field of plant pathology. The prize is normally awarded on the basis of publication in refereed journals.


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Keynote Speakers The Right Honourable James Brendan Bolger, ONZ The Right Hon. James Bolger was Prime Minister of New Zealand from October 1990 to December 1997. During his 25-year career in politics he led the National Party for almost 12 years, was a Minister for 16 years and had three consecutive terms as the country’s head of government. Under his leadership the New Zealand economy was transformed from having the lowest growth rate among the 29 OECD nations to one of the strongest. On 31 December 1997 Mr Bolger was appointed a member of the Order of New Zealand (ONZ), New Zealand’s highest honour. From June 1998 to January 2002 Mr Bolger was New Zealand’s Ambassador to the United States. Since 2002 Mr Bolger has been Chairman of the International Board of the World Agricultural Forum, St Louis, USA. Today Mr Bolger is the Chancellor of the University of Waikato, Chairman of the Board of Directors of the Ian Axford Fellowships in Public Policy, Chairman of the Gas Industry Company Limited, Chairman of Trustees Executors Limited and Chairman of Mt Cook Alpine Salmon Ltd. He is also a Trustee of the Rutherford Trust and President of the NZ/US Council. In August 2009 he became Patron of the New Zealander of the Year Awards. In 2010 Mr Bolger was elected Distinguished Fellow of the New Zealand Institute of Directors. He was previously Chairman of NZ Post, Kiwibank and KiwiRail among other companies. In 1983 he was elected President of The International Labour Organisation in Geneva. Prior to entering national politics in 1972, he was a dairy, beef and sheep farmer and he still chairs the family’s farm company, Hollow Lands Ltd. In 1963 he married Joan Riddell whose work in public life was recognised in 1997 when she was honoured with the award Companion of New Zealand Order of Merit (CNZM). Jim and Joan have 9 children and 13 grandchildren.

Neil McRoberts (UC Davis) In the Quantitative Biology and Epidemiology Lab of the Department of Plant Pathology, epidemiology encompasses elements of biology, social sciences, economics, computer modelling techniques and applied mathematics and statistics. I am interested in how pathogens and hosts interact at the plant level; how those interactions result in the reproduction and dispersal processes of pathogens, driving disease epidemics at field and larger scales; how the required management decisions are reached and how the consequences of management actions feed back into the dynamics of the epidemics over short and long time scales; and how all of those interactions contribute to the sustainability of food production and its environmental impact.

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Keynote Speakers Jen Sheen Jen Sheen grew up in a sugarcane plantation community in a rural area next to the city Pinton in southern Taiwan. The sweet scent in the air and the lush tropic plants in her parents’ gardens are important childhood influence for her choice of studying botany as an undergraduate at National Taiwan University. She started her own research group in the Department of Molecular Biology at Massachusetts General Hospital in 1987 after obtaining her PhD degree at Harvard, and is currently professor in Genetics at Harvard Medical School. Her laboratory is probing plant life by developing simple and powerful tools and strategies to unravel plant signal transduction pathways extending from sensors/receptors to signalling cascades and target genes and proteins that are central to energy and metabolic homeostasis, innate immunity, hormonal regulation, stress adaptation, cell fate specification, plant shape and architecture determination. The investigations are guided by curiosity and the desire to promote the use of green plants as a versatile and fascinating model system for discovering fundamental principles in the regulatory networks of living organisms.

Margaret Dick Margaret Dick joined the Forest Research Institute, Rotorua (now trading as ‘Scion’) in 1972, as one of only five forest pathologists in the country at that time. She specialised in the diagnosis of disorders of forest trees from nursery age to maturity, and although the focus was on exotic plantation species there was always a strong interest in indigenous woody plants. The urban forest was also a component of the programme with time spent on diseases such as the decline of Albizia julibrisson and of Schinus molle. She has been a long-term member of the Dutch elm disease Advisory Committee that has successfully contained Dutch elm disease within Auckland. Evaluation of potential threats posed by overseas pathogens to the New Zealand’s forest estate has also been a component of the work. She was involved in the early detection of Fusarium circinatum (cause of pitch canker disease of pines) in quarantine material in 2003, which prevented the introduction of this unwanted forest fungus into New Zealand. In recent years there has been an increasing focus on diseases of trees caused by members of the genus Phytophthora. This included the study and description of two new Phytophthora species that were unusual in living high up in the crowns of eucalypts. Margaret is a member of the Kauri Dieback Joint Agency Response Technical Advisory Group that is responding to the disease of kauri associated with Phytophthora taxon Agathis. In 2012 Margaret was very honoured (and surprised) to be the recipient of the New Zealand Plant Protection Society Medal.


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Keynote Speakers David Guttman Dr. Guttman received his Ph.D. in microbial evolutionary genetics from Stony Brook University in 1994, followed by postdocs in molecular evolution and molecular plant pathology at the University of Chicago. He started his faculty position at the University of Toronto in 2000, and is currently a Professor with joint appointments in the Departments of Cell & Systems Biology (CSB) and Ecology & Evolutionary Biology. He is also the Associate Chair for Research in CSB and founder and Director of the University of Toronto Centre for the Analysis of Genome Evolution & Function. Dr. Guttman runs a highly diverse research program with three major foci: (1) the evolution of host specificity and virulence in plant pathogenic bacteria; (2) plant and microbial comparative genomics; and (3) studies of the human and plant-associated microbiome. He is best known for elucidating evolutionary and mechanistic processes that determine the course and fate of microbial infections, and characterizing the impact of natural genetic variation on the balance between disease and immunity. These studies have led to numerous awards and honors, including a Canada Research Chair in Comparative Genomics, the Chair of the American Society for Microbiology Division for Evolutionary and Genomic Microbiology, and membership on the editorial boards of prestigious journals such as PLoS Pathogens and PLoS Genetics.

Virginia Stockwell Virginia Stockwell is a research faculty member in the Department of Botany and Plant Pathology at Oregon State University. She obtained her Bachelors degree in Biology from Rutgers University and her Doctorate in Plant Pathology from Colorado State University. She has an active research program on the management of several bacterial diseases of plants, including crown gall of stone fruits and bacterial blight of lilac and blueberry caused by Pseudomonas syringae. Virginia has focused primarily on management of fire blight of pear and apple trees caused by Erwinia amylovora. Fire blight is the most damaging bacterial disease of pear and apple. Fire blight was controlled with antibiotic sprays during bloom until antibiotic-resistant populations of the pathogen emerged. Virginia’s research on fire blight is focused on the development of bacterial biological control agents for disease control, with the long-term goal of identifying sources of variability associated with biological control that impacts efficacy. Currently, her research is aimed at identifying genetic factors that are essential for the pathogen and/or biological control agents to colonize flowers, a key stage in biocontrol and pathogenesis. To better understand the pathogen, she is participating in a collaborative project using next generation sequencing to examine genetic diversity in populations of E. amylovora. Virginia has been active in addressing concerns about the use of antibiotics for disease prevention in plant agriculture, monitoring development of resistance of bacterial plant pathogens to antibiotics, and conducting research on integrated control measures to encourage prudent use of antibiotics and to hinder emergence of antibiotic-resistant populations of bacterial plant pathogens.

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Keynote Speakers Angus Carnegie Dr Angus Carnegie is a Principal Research Scientist with Biosecurity NSW in the NSW Department of Primary Industries. His main roles include managing and conducting forest health surveys and overseeing and improving pest and disease management programs. His areas of expertise include forest health (pests and diseases), forest health surveillance, leaf spot fungi of eucalypts, research on improving pest and disease management strategies, and forest biosecurity. He has collaborative links and research projects with numerous Australian and international colleagues. Dr Carnegie’s involvement in the emergency response to the recent incursion of an exotic disease in Australia (myrtle rust) has strengthened his expertise in biosecurity at the operational, strategic and policy levels. Current research projects include the impact of myrtle rust on key industries and the native environment in Australia and on new and emerging pest and disease issues.

Saskia Hogenhout Research in the Hogenhout lab is aimed at gaining a better understanding of the molecular basis of plant-microbe-insect interactions. Hogenhout’s PhD thesis research (Wageningen University and Research Centre, The Netherlands) focused on molecular aspects of luteovirus-aphid interactions (1994-1999). Hogenhout became an independent Project Leader (Assistant Professor) at The Ohio State University (OSU), USA, after receiving her PhD degree in 1999. At OSU, she started new research projects on leafhopper and planthopper transmission of phytoplasmas and rhabdoviruses, and obtained tenure as Associate Professor in 2005. Hogenhout commenced her Project Leader position at JIC, UK, in June 2007 where she received tenure in October 2012. She received the Derrick Edward Award from The International Organization of Mycoplasmology (IOM) for outstanding research in mycoplasmology comprising global research on human, animal and plant-associated mycoplasma and mycoplasma-like (including phytoplasma) pathogens. Hogenhout’s discoveries include phytoplasma virulence factors (effectors), which interact with conserved plant transcription factors to promote the vegetative growth of plants, thereby encouraging phytoplasma and insect vector colonization. She also established genomic analysis tools for aphids that are used towards understanding the molecular basis of plant-insect interactions and improving plant resistance to insects. Hogenhout has established many fruitful collaborations within the UK and worldwide.


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Keynote Speakers Thierry Candresse Initially trained as an agronomical engineer of INA Paris-Grignon, Thierry Candresse got his PhD on the enzymology of plant viruses replication from the University of Bordeaux 2 in 1984. This was followed by a postdoc on viroids in the laboratory of TO Diener at USDA-ARS in Beltsville, USA. He started his work at INRA Bordeaux in 1986 and is currently director of the Joint Research Laboratory on Fruit Biology and Pathology of the University of Bordeaux and INRA, the French national institute for agronomical research. He is also group leader of the Bordeaux Plant Virology team in this laboratory. His research interests are wide ranging but mostly address two areas of plant virology. The first concerns the study of molecular interactions between viruses and their host plants and, in particular, those controlling the success of viral infection (host susceptibility and genetic resistance, virus resistance-breaking). The second topic, on which he has been most active in recent years, concerns the development of detection and characterization techniques for plant viruses, with practical applications in detection and diagnosis, taxonomy, epidemiology, and more recently on studies on viral communities (metagenomics). These projects have been carried out on a wide range of viruses, with particular emphasis on potyviruses (virus-host interactions) and on fruit tree viruses (virus characterization and diagnosis). In the past few years he has devoted an important part of his activity to the harnessing of next generation sequencing technologies for virus identification and plant virus metagenomics studies.

Neil Boonham Neil currently heads the novel diagnostics team at the Food and Environment Research Agency, and has a background in Plant Virology and Molecular Biology. The research of the team is focused on the development of detection, identification and diagnostic tools for use in centralised laboratory facilities as well as in the field by non-specialist users. Current research focuses in two areas, firstly on the use of next generation sequencing techniques for the detection and characterisation of unknown disease causing agents and secondly in the development and deployment of novel molecular techniques with non-specialists in the field or point of decision making. Neil maintains a keen interest in Virology in particular the interaction between viruses and plant hosts and the evolution of virus species.

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Poster Sessions Tuesday 26th November 6pm - 7pm – Wine & Cheese Poster Session

Wednesday 27th November 1.30pm - 2.30pm | Poster Session 1 Application of New Technologies, Biosecurity, Disease management, Population Genetics

Thursday 28th November 1.30pm - 2.30pm | Poster Session 2 Epidemiology, New and emerging diseases, Plant-pathology interactions, Biological interactions and plant diseases


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Summary programme Monday 25th November 2013 8.30 am - 4.30 pm

Workshop/Tours

2 pm - 5 pm

Registrations Open (Foyer, Owen G Glenn Building)

2 pm - 6 pm

Poster Placement (Foyer, Owen G Glenn Building)

6 pm - 7.30 pm

Welcome Reception at Fale Pasifika

7.30 pm - 9.30 pm

APPS Council Meeting. Dr Elaine Davison. Room 317.

Tuesday 26th November 2013

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8 am - 8.30 am

Poster Placement (Foyer, Owen G Glenn Building)

8 am - 6 pm

Registrations Open

8.30 am - 9 am

Plenary 1: The Right Honourable Jim Bolger, ONZ (Opening Speaker)

9 am - 9.30 am

Plenary 2: Dr Elaine Davison (Presidential Address)

9.30 am - 10.30 am

Concurrent Sessions (1A, 3A, 7A)

10.30 am - 11 am

Morning Tea

11 am - 11.30 am

Plenary 3: Prof Jen Sheen

11.30 am - 12.30 pm

Concurrent Sessions (2A, 4A, 6A)

12.30 pm - 1.30 pm

Lunch

12.30 pm - 1.30 pm

Capability Survey (with lunch)

1.30 pm - 2 pm

Plenary 4: The Ross Beever Memorial Lecture Dr Saskia Hogenhout

2 pm - 2.30 pm

Plenary 5: Dr Margaret Dick

2.30 pm - 3.30 pm

Concurrent Sessions (2B, 4B, 8A)

3.30 pm - 4 pm

Afternoon Tea

4 pm - 4.30 pm

Plenary 6: Dr Neil Boonham

4.30 pm - 6 pm

Concurrent Sessions (3B, 5A, 7B)

6 pm - 7 pm

Wine & Cheese Poster Session

7 pm - 10.30 pm

Social Dinner - Teachers' Eastern Rugby Football Club

PLANT DORMANCY SYMPOSIUM 2013 | Auckland, New Zealand

Summary programme Wednesday 27th November 2013 8 am - 6 pm

Registrations Open

7.30 am - 8.30 am

Presidential Breakfast

8.30 am - 10 am

Concurrent Sessions (2C, 4C, 6B)

10 am - 10.30 am

Plenary 7: Dr Thierry Candresse - sponsored by School of Biological Sciences

10.30 am - 11 am

Morning Tea

11 am - 11.20 am

Plenary 8: MacAlpine Book Dr Doug Parbery

11.20 am - 12.30 pm

Plenary 9: MacAlpine Lecture Dr Shaun Pennycook

12.30 - 1.30 pm

Lunch and Editors' lunch

1.30 pm - 2.30 pm

Poster Session 1

2.30 pm - 3.30 pm

Concurrent Sessions (3C, 5B, 8B)

3.30 pm - 4 pm

Afternoon Tea

4 pm - 4.30 pm

Plenary 10: Ass. Prof. Virginia Stockwell

4.30 pm - 6 pm

Concurrent Sessions (4D, 6C, 7C)

6 pm - 7 pm

APPS General Meeting

7 pm - 11.30 pm

Conference Dinner - Royal NZ Yacht Squadron

Thursday 28th November 2013 8 am - 6 pm

Registrations Open

7.30 am - 8.30 am

APPS Executive Breakfast Meeting

8.30 am - 9.30 am

Concurrent Sessions (2D, 6D, 8C)

9.30 am - 10.30 am

Plenary 11: Getting the Word Out (1) Ruby Andrew , Nick Waipara and Robin Nitschke

10.30 am - 11 am

Morning Tea

11 am - 12 pm

Plenary 11: Getting the Word Out (2) Ass. Prof. Mike Pearson, Melissa Cook, Cherie Gambley

12 pm - 12.30 pm

Plenary 12: Prof. David Guttman

12.30 pm - 1.30 pm

Lunch


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Summary programme 12.30 pm - 1.30 pm

Student Mentor Lunch - Invitation only

1.30 pm - 2.30 pm

Poster Session 2

2.30 pm - 3 pm

Plenary 13: Ass. Prof. Neil McRoberts

3 pm - 3.30 pm

Plenary 14: Dr Angus Carnegie - sponsored by Ministry for Primary Industries

3.30 pm - 4 pm

Afternoon Tea

4 pm - 5 pm

Concurrent Sessions (1B, 2E, 7D)

5 pm - 5.30 pm

APPS Awards

5.30 pm - 5.40 pm

The CRC Plant Biosecurity Student Awards The Springer Student Awards

5.40 pm - 5.50 pm

The Allen Kerr Award

5.50 pm - 6.10 pm

Invitation to Forthcoming Conferences

6.10 pm - 6.20 pm

Acknowledgements and Conference Close

6.20 pm -

Regional Councillors Informal Dinner meeting

Friday 29th November 2013 8.30 am - 4.30 pm

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Workshops/Tours


Programme Monday 25th November 2013 8.30 - 16.30 (variable)

Workshops/Tours

14.00 - 17.00

Registration Open (OGG building foyer)

14.00 - 18.00

Poster placement (OGG building foyer)

18.00 - 19.30

Welcome Reception / Official Opening Welcome by Convenor and Powhiri Maori welcome at Fale Pasifika

19.30 - 21:30

APPS Council Meeting. Dr Elaine Davison. Room 317.

Tuesday 26th November 2013 8.00 - 8.30

Poster placement (OGG Building Foyer)

8.00 – 18.00

Registration Open (OGG Building Foyer)

8.30 - 9.00

PLENARY 1: OPENING SPEAKER Speaker: The Right Honourable Jim Bolger ONZ Chair: Kerry Everett

THEATRE: 098

9.00 - 9.30

PLENARY 2: APPS PRESIDENTIAL ADDRESS Speaker: Dr Elaine Davison, President of the APPS Chair: Kerry Everett

THEATRE: 098

9.30 - 10.30

Concurrent Oral Sessions (15 mins/talk including questions) SESSION 7A: PLANT PATHOGEN INTERACTIONS Chairs: Barry Scott & Alicia Greenhill THEATRE: OGGB3

SESSION 1A: APPLICATION OF NEW TECHNOLOGIES Chairs: Giles Hardy & Trudy Paap THEATRE: OGGB4

SESSION 3A: BIOSECURITY Chairs: Fiona Constable & Wycliff Kinoti THEATRE: OGGB5

9.30 - 9.45

Dothistromin: a fungal virulence factor encoded by a fragmented gene cluster. Rosie Bradshaw, Massey University, New Zealand

Detection of potato potyviruses in aphids caught in water and propylene glycol trap solutions. Ron van Toor, The New Zealand Institute for Plant & Food Research Limited

Identification of trapped insects and associated microbes by next generation sequencing. Simon Bulman, The New Zealand Institute for Plant & Food Research Limited

9.45 - 10.00

ABA2 disjoints ABA pathway into an upstream part required for Bamboo mosaic virus accumulation and a downstream part required for plant resistance. Mazen Alazem, Academia Sinica – IPMB, Taiwan

Hyperspectral leaf response of plant infected with Phytophthora cinnamomi. Zoe-Joy Newby, The Royal Botanic Gardens and Domain Trust, Australia

Increasing the genetic diversity of sugarcane germplasm through continuous introduction of disease-free foreign varieties. Fe Dela Cueva, University of the Philippines, Los Banos


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Programme continued 10.00 - 10.15

Phytophthora root rot of avocado - why are some rootstocks more resistant? Merran Neilsen, Queensland Alliance for Agriculture and Food Innovation, Australia

Citizen science and a smartphone application to monitor the incidence and severity of Quambalaria diseases in Western Australian marri, Corymbia calophyll. Cielito Marbus, Murdoch University, Australia

Defining core pan-genomes of species in ‘‘Candidatus’’ Liberibacter for the development of new diagnostic tools. Grant Smith, The New Zealand Institute for Plant & Food Research Limited

10.15 - 10.30

Investigating the role of strigolactones in pea (Pisum sativum) interactions with soilborne fungal pathogens. Sara Blake, University of Tasmania, Australia

Field evaluation of a bioherbicide for control of parkinsonia (Parkinsonia aculeata) in Australia. Victor Galea, The University of Queensland, Australia

Fusarium vascular infection of oil palm: Epidemiology, genetic diversity and molecular diagnostic tools . Mohd Hefni Rusli, Malaysian Palm Oil Board

10.30 - 11.00

Morning Tea (OGG building foyer)

11.00 - 11.30

PLENARY 3: PLANT PATHOGEN INTERACTIONS Speaker: Prof Jen Sheen, Harvard Medical School, USA Chair: Robin McDiarmid

11.30 - 12.30

Concurrent Oral Sessions (15 mins/talk including questions)

THEATRE: 098

SESSION 4A: DISEASE MANAGEMENT Chairs: Richard Falloon & Hoda Ghazali-Biglar THEATRE: OGGB3

SESSION 6A: NEW AND EMERGING DISEASES Chairs: Lester Burgess & Matthew Laurence THEATRE: OGGB4

SESSION 2A: BIOLOGICAL INTERACTIONS AND PLANT DISEASES Chairs: Eric McKenzie & Claudia Lange THEATRE: 098

11.30 - 11.45

Big achievement from a handful of high performing varieties: a concept in the context of crop health for wheat in Western Australia. Moin Salam, Department of Agriculture and Food Western Australia

Opium poppy mosaic virus, a new member of Umbravirus isolated from Papaver somniferum and Tropaeolum majus in New Zealand. Bénédicte Lebas, Ministry for Primary Industries, New Zealand

What makes Trichoderma rhizosphere competent: A molecular analysis. Artemio Mendoza, BioProtection Research Centre, Lincoln University, New Zealand

11.45 - 12.00

Control of crown canker of passion fruit (Passiflora edulis Sims.) an acute disease problem for New Zealand passion fruit growers. Pia Rheinländer, The New Zealand Institute for Plant & Food Research Limited

Forest trials testing phosphite for control of kauri dieback. Ian Horner, The New Zealand Institute for Plant & Food Research Limited

Species- and strain- specific identification and quantification of root disease suppressive Trichoderma inoculants in cropping soils. Belinda Stummer, CSIRO, Australia

page 22



Enhancing natural disease resistance in Pinus radiata. Tony Reglinski, The New Zealand Institute for Plant & Food Research Limited

Recent emergence of Fusarium dieback of tea (Camellia sinensis) in Sri Lanka and its potential link with Tea Shot Hole Borer (Euwallacea fornicates). Pradeepa Liyanage, Tea Research Institute of Sri Lanka

Dissecting the molecular crosstalk between endophytic fungi and their host plants: Trichoderma as fungal model system. Artemio Mendoza, BioProtection Research Centre, Lincoln University, New Zealand

12.15 - 12.30

Evaluation of Trichoderma isolates to suppress Rhizoctonia diseases on potato. Emily Hicks, Bio-Protection Research Centre, Lincoln University, New Zealand

The disease cycle of alternaria leaf blotch and fruit spot of apple. Dalphy Harteveld, University of Queensland, Australia

Identification of a naturally occurring, mild isolate of Tamarillo mosaic virus. Arnaud Blouin, The New Zealand Institute for Plant & Food Research Limited

12.30 - 13.30

Lunch (OGG building foyer)

12.30 - 13.30

Capability Survey (with lunch) Speaker: Dr Elaine Davison, President of the APPS

THEATRE: 098

13.30 - 14.00

PLENARY 4: ROSS BEEVER MEMORIAL LECTURE Speaker: Dr Saskia Hogenhout, The John Innes Centre, Norwich, UK Chair: Peter Johnston

THEATRE: 098

14.00 – 14.30

PLENARY 5: NEW AND EMERGING DISEASES Speaker: Dr Margaret Dick, SCION, Rotorua, New Zealand Chair: Peter Johnston

THEATRE: 098

14.30-15.30

Concurrent Oral Sessions (15 mins/talk including questions) SESSION 4B: DISEASE MANAGEMENT Chairs: Greg Johnson & Melissa Cooke THEATRE: OGGB3

SESSION 2B: BIOLOGICAL INTERACTIONS Chairs: André Drenth & Amir Daryaei THEATRE: OGGB4

SESSION 8A: POPULATION GENETICS Chairs: Treena Burgess & Maree Horne THEATRE: OGGB5

14.30 - 14.45

Awheto: Initial cultural studies in New Zealand Seona Casonato, The New Zealand Institute for Plant & Food Research Limited

Incidence of Tomato leaf curl virus (ToLCV) in the Philippines and Development of an Infectious DNA Clone for Virus Resistance Screening in Tomato Lolita Dolores, University of the Philippines, Los Banos (UPLB)

Population structures of Neofusicoccum species from nurseries and vineyards indicate movement and origins of infection. Regina Billones-Baaijens, Lincoln University, New Zealand

14.45 - 15.00

Introgression breeding towards the development of nematode resistant sugarcane variety in Australia. Shamsul Bhuiyan, BSES Limited, Australia

Optimization , formulation and stabilisation of the biocontrol yeast Rhodotorula glutinis for controlling strawberry blight. Wafaa Haggag, National Research Centre, Egypt

Myrtle rust in Eucalyptus grandis identification and expression of host defence genes. David Guest, University of Sydney, Australia


page 23


Managing Ganoderma basal stem rot of oil palm: Innovative approach through endophytic microorganism application. Shamala Sundram, Malaysian Palm Oil Board

Germination and bioactivity of Trichoderma atroviride affected by culturing and storage conditions. Amir Daryaei, Bio-Protection Research Centre, Lincoln University, New Zealand

Development of a multiplexed microsatellite library for a population genetics study of Stagonosporopsis tanaceti the cause of ray blight disease of pyrethrum in Australia. Niloofar Vaghefi, The University of Melbourne, Australia

15.15 - 15.30

Optimising pruning wound protection for management of eutypa dieback in grapevine. Matthew Ayres, South Australian Research and Development Institute

Effect of Aureobasidium isolates on mycelium growth of three major bunch rot pathogens of grapes. Sujeewa Rathnayake, Charles Sturt University, NSW, Australia

Simple sequence repeat markers (SSRs) for understanding population structure of Colletotrichum coccodes infecting potato in Australia. Jiang Chang, The University of Melbourne, Australia

15.30 - 16.00

Afternoon Tea (OGG building foyer)

16.00 - 16.30

PLENARY 6: APPLICATION OF NEW TECHNOLOGIES Speaker: Dr Neil Boonham, FERA, York, UK Chair: Bénédicte Lebas

16.30 - 18.00


THEATRE: 098

SESSION 5A: EPIDEMIOLOGY Chairs: Robert Beresford & Kaori Itagaki THEATRE: OGGB3

SESSION 3B: BIOSECURITY Chairs: Lisa Ward & Agnes Simamora THEATRE: OGGB4

SESSION 7B: PLANT PATHOGEN INTERACTIONS Chairs: Matt Templeton & Honour McCann THEATRE: 098

16.30 - 16.45

The effect of postharvest hot fungicidal dip and exogenous ethylene gas application on the incidence of dendritic spot & stem end rot in Kensington Pride (KP) Mangoes. Aslan Qureshi, The University of Queensland, Australia

Development of real-time PCR assays for the detection of the myrtle rust fungus Puccinia psidii. Jeyaseelan Baskarathevan, Ministry for Primary Industries, New Zealand

Botryosphaeriaceae fungi as a potential mycoherbicide for prickly acacia. Ahsanul Haque, The University of Queensland, Australia

16.45 - 17.00

The incidence of Huanglongbing (HLB) on 2-3 year old tangerine trees (Citrus reticulata) grown from disease free nursery stock. Angsana Akarapisan, Chiang Mai University, Thailand

Eradication of Chestnut blight in Victoria Australia. Martin Mebalds, DEPI Biosecurity, Victoria, Australia

Profiles of Fusarium species and mycotoxin on white corn varieties in the Philippines. Cecilia Pascual, Philippine Phytopathological Society

page 24



Seed tuber incidence and pathogenicity of Verticillium species infecting potatoes in Australia. Prakash Vijayamma Ramakrishnan Nair, The University of Melbourne, Australia

Diversity and classification of Phellinus noxius in Queensland and New South Wales. Louise Shuey, Queensland Department of Agriculture, Fisheries and Forestry, Australia

Manipulating the Boom and Bust cycle of blackleg disease of canola saves Australian farmers $20 million in 2012. Angela Van de Wouw, School of Botany, University of Melbourne, Australia

17.15 - 17.30

Seasonal variations in hull rot incidence in almonds. Chin Gouk, Department of Environment and Primary Industries, Australia

Checklists, Quarantine and Trade - continuing challenges for developing countries. Lester Burgess, University of Sydney, Australia

Phyllosphere microbes influence Succinate dehydrogenase activity in mitochondria of tomato. P K Paul, Amity University Uttar Pradesh, India

17.30 - 17.45

Stemphylium grey leaf spot infection of lupins favoured on seedlings in wet and warm conditions. William MacLeod, Department of Agriculture and Food, Western Australia

A new era for government and industry partnerships on biosecurity in New Zealand. Lois Ransom, Government Industry Agreement Secretariat, New Zealand

Mechanisms by which dual NB-LRR genes confer disease resistance in Arabidopsis. Kee hoon Sohn, Massey University, New Zealand

17.45 - 18.00

The effect of elevated temperature on the titre of Barley yellow dwarf virus-PAV in wheat. Narelle Nancarrow, Department of Environment and Primary Industries, Australia

Stripe smuts of grasses: one lineage or high levels of polyphyly. Kryrylo Savchenko, University of Haifa, Israel

Unravelling the cause of Black Pod Syndrome of narrowleafed lupin: Survey data, satisfying Koch's postulates, and next generation sequencing of virus isolates. Monica Kehoe, University of Western Australia

18.00 - 19.00

Wine and cheese Poster session

19.00 - 22.30

Social dinner at the Teachers Eastern Rugby Football Club


page 25

Programme continued Wednesday 27th November 2013 8.00 – 18.00


7.30 - 8.30

Presidential Breakfast (past Presidents and Incoming) Dr Greg Johnson on ISPP and Task Force on Food Security

8.30 - 10.00


CAFETERIA

SESSION 4C: DISEASE MANAGEMENT Chairs: Mark Sosnowski & Zoe-Joy Newby THEATRE: OGGB3

SESSION 6B: NEW AND EMERGING DISEASES Chairs: Barbara Hall & Sunil Singh THEATRE: OGGB4

SESSION 2C: BIOLOGICAL INTERACTIONS AND PLANT DISEASES Chairs: Hayley Ridgeway & Philippa Child THEATRE: OGGB5

8.30 - 8.45

Containment and eradication of Phytophthora cinnamomi in natural ecosystems. Bill Dunstan, Murdoch University, Australia

Melon necrotic spot virus detected on watermelons in New South Wales. Len Tesoriero, NSW Department of Primary Industries, Australia

Trichoderma koningiopsis (Tr905) suppression of a barley root disease complex alters the species composition and intraspecific genetic structure of pathogen populations. Rosemary Warren, CSIRO, Australia

8.45 - 9.00

Impact of fungicide resistance in Venturia inaequalis on control of apple scab in New Zealand. Robert Beresford, The New Zealand Institute for Plant & Food Research Limited

Pseudomonas syringae pv. porri: a new pathogen of Australian onions. Rebecca Roach, Department of Agriculture, Fisheries and Forestry, Australia

Why mycologists should be interested in viruses: The interaction and effects of mycoviruses on their fungal hosts. Michael Pearson, The University of Auckland, New Zealand

9.00 - 9.15

Heat and chemical treatments to reduce systemic infection of tissue culture derived boysenberry plants by the downy mildew pathogen Peronospora sparsa. Anusara Herath Mudiyanselage, Ecology Department, Lincoln University, New Zealand

Understanding the role of and determining practical management solutions for Quambalaria coyrecup canker disease, the cause of Corymbia calophylla (marri) decline in the south-west of Western Australia. Trudy Paap, Murdoch University, Australia

Seasonal and regional variation of Botrytis in New Zealand vineyards. Peter Johnston, Landcare Research, New Zealand

9.15 - 9.30

Evaluation of PCR methods for detection and identification of Xylella fastidiosa in Coffea sp. plant. Françoise Poliakoff, ANSES - Plant Health LaboratoryFrance

Emergence of Pestalotiopsis species as the causal agent of raceme blight and dieback of macadamia Femi Akinsanmi, QAAFI, The University of Queensland, Australia

Biological interactions of mites and microbes associated with gall formation in Scotch Broom Cytisus scoparius. Chantal Probst, Landcare Research, New Zealand

page 26



Application of the PBcast model for timing fungicide sprays to control Phytophthora blight of pepper. Eunwoo Park, Seoul National University, Korea

Biological and molecular characteristics and geographic spread of the different biovars of Pseudomonas syringae pv. actinidiae. Joel Vanneste, The New Zealand Institute for Plant & Food Research Limited

Transcriptome analysis of the beneficial fungus Trichoderma virens during interaction with Zea mays. Robert Lawry, Lincoln University, New Zealand

9.45 - 10.00

Protection of apple budding wounds from European canker. Reiny Scheper, The New Zealand Institute for Plant and Food Research Ltd

Phytophthora pluvialis and its relation to red needle cast disease of Pinus radiata in New Zealand. Nari Williams, SCION - New Zealand Forest Research Institute

Identifying targets for sustainable control of Sclerotinia diseases. Alicia Greenhill, La Trobe University, Australia

10.00 - 10.30

PLENARY 7: APPLICATION OF NEW TECHNOLOGIES THEATRE: 098 Speaker: Dr Thierry Candresse, INRA, Bordeaux, France - Sponsored by School of Biological Sciences Chair: Mike Pearson

10.30 - 11.00


11.00 - 11.20

PLENARY 8: MACALPINE BOOK Speaker: Dr Doug Parbery Chair : Kerry Everett

11.20 - 12.30

PLENARY 9: MACALPINE LECTURE THEATRE: 098 Speaker: Dr Shaun Pennycook, Landcare Research, Auckland, New Zealand Chair: Kerry Everett

12.30 - 13.30


12.30 - 13.30

Editors Lunch

13.30 - 14.30

POSTER SESSION 1 OGG BUILDING FOYER Application of new technologies, Disease management, Epidemiology, Population genetics

14.30 - 15.30


14.30 - 14.45

THEATRE: 098

SESSION 5B: EPIDEMIOLOGY Chairs: Suvi Viljanen-Rollinson & t.b.c. THEATRE: OGGB3

SESSION 3C: BIOSECURITY Chairs: David Teulon & Kieren Arthur THEATRE: OGGB4

SESSION 8B: POPULATION GENETICS Chairs: Kim Plummer & Dalphy Harteveld THEATRE: OGGB5

The development of an elsinoe infection risk model for apple in New Zealand. Peter Wood, The New Zealand Institute for Plant & Food Research Limited

Keeping one step ahead of invasive species: Using an integrated framework to screen and target species, for detailed biosecurity risk assessment. Sunil Singh, CSIRO Ecosystem Sciences, Australia

Phylogeny and Secreted In Xylem (SIX) gene characterisation of Fusarium oxysporum.sp. canariensis in Australia. Matthew Laurence, The Royal Botanic Gardens and Domain Trust, Australia


page 27


Temperature and moisture content stimulate the growth of fungi on healthy stored grain over time. Kirsty Bayliss, Murdoch University, Australia

Recent changes in Colletotrichum taxonomy. Bevan Weir, Landcare Research, New Zealand

Next Generation Sequencing reveals unexplored Phytophthora diversity in Australian soils. Treena Burgess, Murdoch University, Australia

15.00 - 15.15

Sensitivity analysis and uncertainty in a species distribution model. Hossein Narouei Khandan, Lincoln University, New Zealand

Dutch elm disease in New Zealand: From eradication to management. Beccy Ganley, SCION - New Zealand Forest Research Institute

An expanded AvrLm6-like gene family in scab fungi. Jason Shiller, La Trobe University, Australia

15.15 - 15.30

Modeling the impact of disease resistance on rice yields in the Philippines and Indonesia. Adam Sparks, International Rice Research Institute, Philippines

Mango malformation in the Northern Territory of Australia. Lucy Tran-Nguyen, Department of Primary Industry and Fisheries, NT, Australia

Dynamics of Dasheen mosaic virus population structure in evolutionary space and time. Wee-Leong Chang, Auckland University of Technology, New Zealand

15.30 - 16.00


16.00 - 16.30

PLENARY 10: DISEASE MANAGEMENT Speaker: Ass. Prof. Virginia Stockwell, USDA, Oregon State, USA Chair: Nick Waipara

16.30 - 18.00


THEATRE: 098

SESSION 7C: PLANT PATHOGEN INTERACTIONS Chairs: Rosie Bradshaw & Lucilene Santos THEATRE: OGGB3

SESSION 6C: NEW AND EMERGING DISEASES Chairs: Colleen Higgins & Gardette Valmonte THEATRE: OGGB4

SESSION 4D: DISEASE MANAGEMENT Chairs: Christine Horlock & Monica Kehoe THEATRE: 098

16.30 - 16.45

Quantitative measurement of the impacts of virus infection in Arabidopsis thaliana. Kieren Arthur, The New Zealand Institute for Plant & Food Research Limited

Myrtle rust - symptoms, impact and spread in Queensland, Australia. Fiona Giblin, University of the Sunshine Coast, Australia

Heat and dessication kills Pseudomonas syringae pv. actinidiae on kiwifruit pollen. Kerry Everett, The New Zealand Institute for Plant & Food Research Limited

16.45 - 17.00

In search of resistance to grapevine trunk diseases. Mark Sosnowski, South Australian Research and Development Institute

Pathogenicity of Pythium spp. isolated from ginger fields in Australia. Duy Le, The University of Queensland, Australia

Effect of biofumigation and arbuscular mycorrhizal inoculation on specific apple replant disease (SARD). Eirian Jones, Lincoln University, New Zealand

17.00 - 17.15

Variable disease resistance to Sclerotinia sclerotiorum in traditional New Zealand / Maori sweet potato cultivars. Rebekah Fuller, The University of Auckland, New Zealand

Determining the origin of the emerging pathogen, Phytophthora multivora. Treena Burgess, Murdoch University, Australia

Selection and characterisation of Trichoderma isolates for suppression of Pratylenchus in wheat roots. Mark Braithwaite, BioProtection Research Centre, Lincoln University, New Zealand

page 28



Characterisation of toxins from Pyrenophora teres f. teres in net form net blotch disease of barley. Amanda Able, The University of Adelaide, Australia

A new Phytophthora disease from nurseries in Western Australia. Agnes Simamora, Murdoch University, Australia

Pratylenchus teres Western Australia's home grown root lesion nematode (RLN). Sarah Collins, Department of Agriculture and Food Western Australia

17.30 - 17.45

Internal movement of Pseudomonas syringae pv. actinidiae through symptomless kiwifruit tissues. Joy Tyson, The New Zealand Institute for Plant & Food Research Limited

Blackberry decline along the Warren and Donnelly Rivers: a major disease of Rubus anglocandicans in south-west Australia. Giles Hardy, Murdoch University, Australia

Management of Grapevine leafroll-associated virus 3 in New Zealand. Daniel Cohen, The New Zealand Institute for Plant & Food Research Limited

17.45 - 18.00

Crop growth enhancement and disease control using nurseryinoculated Trichoderma root endophytes isolated from local healthy plants. Robert Hill, Bio-Protection Research Centre, Lincoln University, New Zealand

First report of ‘‘Candidatus’’ Liberibacter solanacearum in carrot in France. Franҫoise Poliakoff, ANSES - Plant Health LaboratoryFrance

Effects of susceptible and resistant cultivars on populations of the potato cyst nematode Globodera rostochiensis Ro1 and on potato yields in Victoria, Australia. Rudolf de Boer, Department of Environment and Primary Industries, Victoria, Australia

18.00 - 19.00

APPS GM

19.00 - 23.30

Conference Dinner at the Squadron Ballroom and Dinghy Locker, at the Royal New Zealand Yacht Squadron


THEATRE: 098

page 29

Programme continued Thursday 28th November 2013 8.00 – 18.00


7.30 – 8.30

APPS Executive Breakfast Meeting (current and incoming Management Committees)

8.30 – 9.30


CAFETERIA

SESSION 2D: BIOLOGICAL INTERACTIONS AND PLANT DISEASES Chairs: Amanda Able & Robert Lawry THEATRE: OGGB3

SESSION 6D: NEW AND EMERGING DISEASES Chairs: Beccy Ganley & Cielito Marbus THEATRE: OGGB4

SESSION 8C: POPULATION GENETICS Chairs: Paul Taylor & Niloofar Vighefi THEATRE: OGGB5

8.30 – 8.45

A study of Botrytis Virus X transmission and vegetative incompatibility in Botrytis cinerea. Gregor Kolbe, The University of Auckland, New Zealand

Exotic pests and pathogens detected by general surveillance in Victoria – 2010 to 2013. Robert Holmes, Department of Environment and Primary Industries Victoria(DEPI), Australia

Dasheen mosaic virus and Vanilla mosaic virus: using deep sequencing to compare virus strains and identify functionally important genome regions. Colleen Higgins, Auckland University of Technology, New Zealand

8.45 – 9.00

Drought tolerance in endophyte-infected ryegrass – a transcriptomics study. Yanfei Zhou, Institute of Fundamental Sciences, Massey University, New Zealand

Species and subclade composition of Leptosphaeria spp. populations causing blackleg in brassica crops in New Zealand. Suhaizan Lob, Lincoln University, New Zealand

Molecular characterisation of Grapevine leafroll-associated virus 3 variants in New Zealand. Kar Mun Chooi, The New Zealand Institute for Plant & Food Research Limited

9.00 – 9.15

Biological control of black rot of Brassica by a potential biocontrol agent- Paenibacillus sp. Hoda Ghazali-Biglar, BioProtection Research Centre, Lincoln University, New Zealand

‘‘Candidatus’’ Liberibacter solanacearum: its interactions with insect and plant hosts and their impacts on potato production. Andrew Pitman, The New Zealand Institute for Plant & Food Research Limited

Genetic diversity and genetic structure of Fusarium oxysporum f. sp. ubter the causal agent of yellows and wilt of sesame in Fars Province in Iran by using IGS-RFLP. Seddiqe Mohammadi, Shiraz Islamic Azad University, Iran

9.15 – 9.30

Evolution of Rhynchosporium commune on barley grass. Celeste Linde, The Australian National University

Black Scab of Jojoba (Simmondsia chinensis): a new emerging disease in Australia caused by a new pathotype of Elsinoe australis. Amir Sohail, Charles Sturt University, Australia

Identity, genetic diversity and relative virulence of botryosphaeriaceous species causing blueberry decline in New Zealand. Hayley Ridgway, Lincoln University, New Zealand

9.30 – 10.30

PLENARY 11: GETTING THE WORD OUT THEATRE: 098 Speaker on “Science-to-grower communications in the wine industry – a case study”: Ruby Andrew, New Zealand Winegrowers Speaker on “The importance of the role of communication in science when industry is faced with a crisis”: Robin Nitschke, Manager of the Tamarillo Growers’ Association Speaker on “How we use science communication to increase public engagement and behaviour change – lessons learnt from the management of kauri dieback”: Nick Waipara, Auckland Council Chair: Robin MacDiarmid

page 30


Programme continued 10.30 – 11.00


11.00 – 12.00

PLENARY 11 (CTD): GETTING THE WORD OUT THEATRE: 098 Speaker on “Science to Science”: Ass. Prof. Mike Pearson, PestNet Speaker on Plant Pathology International Development: A Year in the Kingdom of Tonga: Melissa Cook, Tonga Speaker on Area wide management of Tomato yellow leaf curl, Potato leafroll and Tomato spotted wilt viruses in Bowen, Australia: Cherie Gambley, Department of Agriculture, Fisheries and Forestry, QLD, Australia Chair: Robin MacDiarmid

12.00 – 12.30

PLENARY 12: POPULATION GENETICS Speaker: Prof. David Guttman, University of Toronto, USA Chair: Rob Taylor

12.30 – 13.30


12.30 – 13.30

HAL Student Mentor Lunch (Presentation of HAL awards)

13.30 – 14.30

Poster Session 2 (OGG building foyer) Biosecurity, New and emerging diseases, Plant pathogen interactions, Biological interactions & plant diseases

14.30 – 15.00

PLENARY 13: EPIDEMIOLOGY Speaker: Ass. Prof. Neil McRoberts, University of California, Davis, USA Chair: Wellcome Ho

15.00 – 15.30

PLENARY 14: BIOSECURITY THEATRE: 098 Speaker: Dr Angus Carnegie, Department of Primary Industries, New South Wales, Australia - Sponsored by Ministry for Primary Industries Chair: Wellcome Ho

15.30 – 16.00


16.00 – 17.00


16.00 – 16.15

THEATRE: 098

DECIMA GLENN, ROOM 310

THEATRE: 098

SESSION 7D: PLANT PATHOGEN INTERACTIONS Chairs: Phil O’Brien & Tracey Immanuel THEATRE: OGGB3

SESSION 2E: BIOLOGICAL INTERACTIONS AND PLANT DISEASES Chairs: Eileen Scott & Fumi Fukoda THEATRE: OGGB4

SESSION 1B: APPLICATION OF NEW TECHNOLOGIES Chairs: Joe Win & Jason Shiller THEATRE: OGGB5

Role of OASTL-A1 in plant immunity and interaction with NBS-LRR immune receptor. Jibran Tahir, Massey University, New Zealand

Three diseases of potato plants caused by Spongospora subterranean powdery scab on tubers, galls on roots, zoosporangia in root cells (root malfunction). Richard Falloon, New Zealand Institute for Plant & Food Research Limited

Can a single genomic difference result in a better biocontrol agent? Claudia Lange, BioProtection Research Centre, Lincoln University, New Zealand


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Programme continued 16.15 – 16.30

Secretome analysis identifies conserved putative effectors of the fungal pathogen Ciborinia camelliae. Matt Denton-Giles, Massey University, New Zealand

Protecting commercial Australian potato genotypes from Verticillium wilt through identification of sources of resistance. Veradina Dharjono, The University of Melbourne, Australia

Application of viability PCR for the selection detection of live pathogens in a quarantine setting. Robert Taylor, Ministry for Primary Industries, New Zealand

16.30 – 16.45

Towards a molecular tool for identifying virus infected plants. Sonia Lilly, The New Zealand Institute for Plant & Food Research Limited

Insects as vectors of Quambalaria pitereka the significant shoot, flower and bud blight pathogen of Corymbia calophylla in southwest Western Australia. Briony Williams, Murdoch University, Australia

The detection of brassicainfecting viruses in the aphids Myzus persicae and Brevicoryne brassicae. Sarah Thompson, The New Zealand Institute for Plant & Food Research Limited

16.45 -17.00

Analysis of the accessory genome of the kiwifruit pathogen Pseudomonas syringae pv. actinidiae. Matthew Templeton, The New Zealand Institute for Plant & Food Research Limited

Friends don’t eat friends: loss of endophyte mutualism triggers activation of host degradation. Carla Eaton, Massey University, New Zealand

Preliminary results on the use of electronic nose for the early diagnosis of bacterial canker of kiwifruit. Francesco Spinelli, University of Bologna, Italy

17.00 – 17.30

APPS Awards: Fellows and honorary members Chair: Professor Eileen Scott

THEATRE: 098

17.30 – 17.40

The CRC Plant Biosecurity Student Awards Chair: Dr Michael Robinson The Springer Student Awards

THEATRE: 098

17.40 – 17.50

The Allen Kerr Award Chair: Professor Eileen Scott

THEATRE: 098

17.50 – 18.10

Invitation to Forthcoming Conferences Dr Phil O’Brien

THEATRE: 098

18.10 – 18.20

Acknowledgements and Conference Close

THEATRE: 098

18.20 -

Regional Councillors Informal Dinner meeting Dr Christine Horlock

Friday 29th November 2013 8.30 – 16.30 (variable)

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Workshops/Tours


ORAL PRESENTATION ABSTRACTS

PLENARY SPEAKERS

Don’t forget the plants!

Plant innate immune signaling networks

Dr Elaine Davison

Prof Jen Sheen

[email protected]

[email protected]

Department of Environment and Agriculture, Curtin University, Perth, GPO Box U1987, Western Australia 6845

Department of Genetics, Harvard Medical School, Department of Molecular Biology and Center for Computational & Integrative Biology, Massachusetts General Hospital, Boston, MA, USA

The plant disease triangle is one of the fundamental concepts that underlie the understanding and management of plant disease. It presupposes knowledge of the host, the pathogen and the environment, how these interact, and how they can be modified to minimise the risk of severe disease developing. Agricultural crops are well known; plant pathologists have access to an extensive literature on their structure, physiology, nutritional requirements and genetics all of which feed into practical control measures. Native plants in natural ecosystems, however, are a different proposition because so little is known about them. How can we understand a diseased plant without a detailed knowledge of a healthy one? This is the situation confronting me when starting to work on jarrah dieback, so that I have spent some time investigating jarrah (Eucalyptus marginata) in addition to working with the introduced soil-borne pathogen Phytophthora cinnamomi. This journey has been full of surprises.

Plant innate immunity is triggered by broadly conserved microbe-associated molecular patterns (MAMPs) and specific pathogenic effectors, which confer tolerance or resistance to a broad spectrum of microbes and pathogens. MAMPs are perceived by cell-surface pattern recognition receptors (PRRs) encoded by receptor-like kinases (RLKs) or receptor-like proteins (RLPs), whereas pathogenic effectors are delivered into plant cells and detected by intracellular NB-LRRs (NLRs) immune sensors. Despite the receptor diversity in MAMP and effector perception evolved to capture the potentially infinite invaders, the intracellular signaling mechanisms appear to converge and establish differential transient or prolonged plant protection against infection. It remains unknown how MAMPPRR signaling and effector-NLR signaling are intertwined or distinguished in the dynamic and complex plant innate immune signaling networks. I will present our efforts in developing integrated approaches, which enabled detailed molecular, chemical, biochemical, genetic and genomic dissection of signal transduction mechanisms underlying plant innate immune responses. Novel insights into the dynamic and differential calcium signaling in PTI (pattern-triggered immunity) and ETI (effector-triggered immunity) will be highlighted.


page 35

PLENARY SPEAKERS

Insect vectors and vector-borne disease agents of plants - the surprising dynamics of interactions among three unrelated organisms

Dr Margaret Dick [email protected]

Dr Saskia A. Hogenhout

Scion, New Zealand Forest Research Institute Ltd., Rotorua, New Zealand

[email protected] Department of Cell and Developmental Biology, John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK

Insects are the main consumers of plants and are responsible for an estimated 15% of global crop losses. In addition, particularly sap-feeding insects such as aphids, whiteflies and leafhoppers, transmit a variety of pathogens and hence may be viewed as the mosquitoes of plants. Remarkably, more than 80% of the insect species are regarded as specialists with less than 10% feeding on plants in more than 3 plant families. Thus, most plants are resistant to most insect herbivores. Research in my laboratory has demonstrated that insects modulate plant processes to efficiently colonize plants. We have identified virulence proteins (effectors) in aphid saliva that promote aphid colonization on plants. Intriguingly insectvectored pathogens often assist in the modulation of plant processes to the benefit of both the insect vectors and the pathogens. The obligate leafhopper-transmitted phytoplasmas have effectors that promote leafhopper colonization thereby increasing the chance of phytoplasma transmission to other plants. Phytoplasma effector protein SAP11 destabilizes TCP transcription factors resulting in increased stem production and altered leaf development and reduced jasmonate (JA) synthesis, while effector protein SAP54 destabilizes MADSbox transcription factors leading to the conversion of flowers into leaves and delayed plant senescence. Leafhoppers feed and lay eggs on green plant tissues and are sensitive to JA. Both phytoplasma effectors promote leafhopper feeding and reproduction contributing to a 60% increase in the number of insect vectors on phytoplasma-infected plants. Thus, both insects and insect-transmitted pathogens produce effectors that promote insect colonization on plants. Overall this research will lead to a greater understanding of plant defence mechanisms to insect herbivores that can be used towards approaches to improve crop resistance to insects.

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New diseases of woody plants – a New Zealand perspective

Plant communities have evolved in association with cohorts of potentially pathogenic microorganisms which generally cause little or no damage to their hosts. However introduction of these microorganisms to another part of the world, where different host species with no resistance are exposed to a pathogen may lead to a new, sometimes devastating, disease. The movement of organisms into new environments also provides the opportunity for the formation of hybrids, new species or subspecies that are potentially pathogenic to new host species or host genera. Hybridisation between long-established related species may also, though rarely, result in a new pathogen. Climate change presents another avenue for altering virulence patterns of existing pathogens, whether by altering host response mechanisms or by affecting expression of virulence genes. Mutation or recombination of genetic material during meiosis can affect pathogenicity of microorganisms, likewise the acquisition of new effector proteins. The plant-based component of New Zealand’s economy is currently dependent on exotic plant species whether the industry be forestry, agriculture or horticulture. New diseases that have had a marked effect in New Zealand in recent decades have fallen into the categories of both known and undescribed organisms. Measures to prevent entry of causal agents of known diseases of these hosts that occur in overseas countries are embedded in import legislation. Notwithstanding regulations incursions happen and sometimes with devastating impact e.g. the bacterial disease of kiwifruit caused by Pseudomonas syringae pv. actinidiae. The urban forest has also been affected, particularly in Auckland (New Zealand’s primary gateway for people traffic and imports). Indigenous plants have been largely unaffected to date though they are not exempt, with the Phytophthora root disease of Agathis australis (kauri) as the current high-profile example. Ways in which ‘new’ pathogens and new diseases emerge will be discussed and illustrated with examples, primarily from the New Zealand experience and with a focus on woody plants.


PLENARY SPEAKERS

Application of New Technologies Dr Neil Boonham [email protected] The Food and Environment Research Agency, Sand Hutton, York, North Yorkshire. YO41 1LZ. UK

Detection and identification of plant pathogens relies upon a broad range of techniques and skills, combining traditional culture and taxonomic skills with modern molecular based methods. Whilst usually delivered as a laboratory service methods that can be performed in the field are starting to reach maturity. The challenge for many laboratories is selecting an from a plethora of methods which all have equally high performance, in addition deciding if the biggest benefits can be gained from delivering testing in the field or in the laboratory. Delivering services in the field offers obvious advantages in terms of speed of analysis and potentially reduced costs in terms of overheads if not individual analysis. However, pushing testing into the field may directly or inadvertently serve to reduce the size of laboratory services. These staff are important knowledge custodians when there are new pest incursions, equally centralised testing laboratories are capable of testing the vast numbers of samples generated during outbreaks. This provides a policy conundrum and a delicate balance needs to be reached between retaining expertise deployed during times of crisis and delivery of more cost effective dayto-day screening services. Concurrent with the maturation of field testing technologies is the rapid pace at which Next Generation Sequencing technologies are developing and the potential they bring in delivering generic approaches in the first instance for the investigation of new or intractable diseases. The developments though may be more far reaching, cost per nucleotide is a new currency and as it drops it brings with it the potential for ultra-high throughput, very low cost per sample testing which would have been unheard of even five years ago when we started exploring the potential of NGS.

Contrasted patterns of phytoviral metagenomes in wild and agricultural environments Dr Thierry Candresse [email protected] T. Candresse(1,2), A. Marais(1,2), C. Faure(1,2), S. Theil(1,2), L. Svanella-Dumas(1,2), S. Carrere(3,4), B. Bergey(1,2), C. Couture(1,2), Y. Laizet(1,2) INRA, UMR 1332 BFP, BP81, 33883 Villenave d’Ornon cedex, France. Université de Bordeaux, UMR 1332 BFP, BP81, 33883 Villenave d’Ornon cedex, France. (3) INRA, Laboratoire des Interactions Plantes-Microorganismes (LIPM), UMR441, F-31326 Castanet-Tolosan, France. (4) CNRS, Laboratoire des Interactions Plantes-Microorganismes (LIPM), UMR2594, F-31326 Castanet-Tolosan, France. (1) (2)

The development of novel sequencing techniques allows an unprecedented access to viral metagenomes and, in particular, to the yet poorly studied communities of phytoviruses in plant populations. We have studied two very different ecological settings, agricultural plots in south western France and the uncultivated Kerguelen Islands, the second most isolated archipelago on earth. The results obtained in the Kerguelen Islands demonstrate a very low diversity of single-stranded RNA (ssRNA) viruses and a large diversity of novel double-stranded RNA (dsRNA) viruses belonging to the families Totiviridae, Partitiviridae and Endornaviridae and the recently proposed Amalgamaviridae family. A similar diversity of novel dsRNA viruses was observed in SW France with, in addition, a wide range of both known and novel ssRNA viruses (Alpha- and Betaflexiviridae, Bromoviridae, Closteroviridae, Luteoviridae, Potyviridae, Secoviridae, Tombusviridae…). Remarkably, at the sampling intensity used, close to half of the weed species were found to be free of infection by ssRNA viruses while the number of novel ssRNA agents remained roughly comparable to the number of known ones, suggesting that in the studied agricultural ecosystem a significant proportion of ssRNA viruses has already been described through classical approaches. Simultaneous presence of viruses in crops and in neighboring weeds was observed, suggesting viral spillover from crop to weeds but not allowing to draw conclusions on potential reservoir roles. These first efforts illustrate the potential of these approaches to analyze the phytoviral diversity as a first step towards the identification of the drivers shaping this diversity and the resulting viral communities.


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PLENARY SPEAKERS

Fungal names in flux Dr Shaun Pennycook [email protected] Research Associate, Manaaki Whenua Landcare Research, Private Bag 92 170, Auckland 1142, New Zealand

A discourse is presented on fungal nomenclature: its origin, history, and governance; its utility; how names should be formed and cited; why names change; the type principle; the priority principle; invalid and illegitimate names; sanctioned names; and the dual nomenclature of anamorphic and teleomorphic names. The major changes affecting fungal nomenclature as a consequence of emendments to the International Code of Nomenclature (ICN), ratified at the XVIIIth International Botanical Congress, Melbourne 2011, are described; in particular, the revolutionary abolition of dual nomenclature (“one fungus, one name”) is discussed, with consideration and speculation on the possible composition of the lists of “accepted” and “rejected” names being prepared by special sub-committees for each group of fungi.

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Management of bacterial diseases of plants: successes and challenges Ass Prof Virginia Stockwell [email protected] Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR 97330 USA

Control of bacterial diseases of plants is difficult, in part, because there are few effective materials to suppress growth of bacterial pathogens on plants. Antibiotics are effective preventatives for a few plant diseases, but emergence of resistance and regulatory constraints threaten their long-term use. Biological control is an attractive alternative. Agrobacterium radiobacter K84 (and its derivative K1084) has been used with noteworthy success for prevention of crown gall of stone fruit rootstocks in nurseries. Adoption of other biocontrol systems by growers is hampered, in part, due to unexplained variation in efficacy. We study factors that impact efficacy of the biological control agents Pseudomonas fluorescens A506 and Pantoea vagans C9-1 for fire blight of apple and pear flowers caused by Erwinia amylovora. A506 and C9-1 suppress disease by pre-emptive exclusion and production of peptide antibiotics, respectively. Combining A506 and C9-1 did not improve efficacy compared to single strains. We found that an extracellular protease of A506 inactivated the peptide antibiotic of C9-1. Biological control of fire blight was improved by altering a single factor (protease production) mediating the outcome of interactions between C9-1 and A506 and the pathogen. Because microbial interactions are complex and rarely determined by a single factor, we are now using genomicsenabled approaches to characterize interactions between the biocontrol agents and the pathogen on flowers. Identifying factors shaping interactions between microorganisms in agroecosystems may lead to methods to improve the efficacy, consistency, and adoption of biological control for management of bacterial diseases of plants.


PLENARY SPEAKERS

Dissecting the Co-Evolutionary Arms Race between Bacterial Effectors and the Plant Immune System Prof David S. Guttman [email protected] Department of Cell & Systems Biology, University of Toronto, Toronto, Ontario Canada

The YopJ/HopZ family of type III secreted effector proteins is evolutionarily diverse and widely distributed among both plant and animal pathogens. We have previously shown that the family diversified in the plant pathogenic bacterium Pseudomonas syringae via both mutational processes during vertical descent from the ancestral P. syringae, as well as through horizontal transfer from ecologically similar pathogens into five distinct allele groups. We also have shown that the most ancestral allele (HopZ1a) is consistently recognized by the plant resistance protein, ZAR1, and that this interaction induces ETI. Here we discuss genetic screens and heterologous assays to identify virulence targets of HopZ1. We first show that HopZ1a interacts with the plant microtubule network, and demonstrate that it is an acetyltransferase that acetylates itself and tubulin. Furthermore, HopZ1a requires its acetyltransferase activity to disrupt the Arabidopsis microtubule network and the secretory pathway as well as to suppress cell wall-mediated defense. We also demonstrate that HopZ1a directly interacts with and acetylates a previously uncharacterized protein kinase (ZED1), which is encoded within a tandemly arrayed family of related kinases, and which also directly interacts with and is required for ZAR1 activation.

The Structure of Diagnostic Information Ass Prof Neil McRoberts [email protected] G. Hughes(1), N. Mcroberts(2) Crop and Soil Systems, SRUC, West Mains Road, Edinburgh, EH9 3JG, UK (2) Plant Pathology Department, University of California, Davis, Davis CA 95616-8751, USA (1)

Diagnosis is characterized as an exercise in classification, where the task is to assign a crop to a risk group as a basis for evidence-based crop protection decision making. Underlying the process of diagnostic decision making is Bayesian updating of probabilities. Alongside updating of probabilities, assessments of diagnostic information allow further description of the characteristics of diagnostic tests, and of the predictions made on the basis of test outcomes. To this end, the paper demonstrates potential uses of the information quantities entropy, expected mutual information, specific information and relative entropy. The applications are described analytically, graphically (by means of iso-information contour plots and information graphs) and by discussion of example epidemiological scenarios. Some conjectures are also offered on how information quantities might be used to provide a formal means to analyze resistance to adoption of decision aids among groups of decision makers who are recipients of support by extension workers.


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PLENARY SPEAKERS

Puccinia psidii (myrtle rust): preparing for an invasion Dr Angus J. Carnegie [email protected] Biosecurity NSW, NSW Department of Primary Industries, PO Box 242, Parramatta, NSW 2124, Australia.

Puccinia psidii (guava/eucalyptus/myrtle rust) is an invasive rust with a host range encompassing over 350 species in 65 genera of Myrtaceae. Described in Brazil over a century ago, it slowly invaded countries in South and Central America, and in the mid-1970s reached Florida (USA). Over the past decade it has invaded Hawaii (2005), China and Japan (2009), Australia (2010) and South Africa and New Caledonia (2013). Rust spores can be moved internationally via infected plant material and commonly on clothes of international travellers as well as on cargo; the former mode of transport can be regulated, thus restricting the highest risk of invasion. However, it is only a matter of time before P. psidii reaches New Zealand. Early detection is essential in any potential eradication attempt. Lessons learnt from the invasion of myrtle rust into Australia will be discussed in light of the threat of P. psidii to New Zealand. A speedy and well resourced and coordinated program is required for any eradication attempt. Staff (e.g. biosecurity, pathologists, botanists) need to be identified, as well as systems in place to access them. Strong links with industry bodies and interest groups are required. Assume all species of Myrtaceae are a host. Don’t assume that symptoms of P. psidii are obvious to find. The potential impact of P. psidii is real: myrtle rust has now spread along the eastern seaboard of Australia and in less than 3 years has caused significant impact to key Myrtaceae and threatened species.

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GETTING THE WORD OUT

Area wide management of Tomato yellow leaf curl, Potato leafroll and Tomato spotted wilt viruses in Bowen, Australia

Plant Pathology & International Development: A Year in the Kingdom of Tonga

Dr Cherie Gambley

Ms Melissa Cook

Cherie Gambley(1), Rebecca Roach(1), Denis Persley(1), Murray Sharman(1)

Melissa Cook

Department of Agriculture, Fisheries and Forestry, QLD [email protected]

(1)

Department of Agriculture, Forestry and Fisheries, QLD

Tomato yellow leaf curl virus (TYLCV; Begomovirus) and Potato leafroll virus (PLRV; Polerovirus) are emerging concerns for tomato production in the Bowen region of north Queensland. Both viruses were confirmed present in Bowen in 2011 with high incidences recorded for some crops in 2012. TYLCV is transmitted by the Silverleaf whitefly (SLW) and PLRV by several aphid species, including the Green peach aphid (GPA). GPA has, in recent seasons, developed large populations in the Bowen district and has proven difficult to control. Tomato spotted wilt virus (TSWV; Tospovirus) is an ongoing concern for the district and due to recent switches to the use of non-TSWV resistant varieties, either to combat TYLCV or due to unavailability of seed, economic losses to this virus also increased. A recent workshop on the epidemiology and management of whitefly-transmitted viruses held in Brisbane (October 2012) demonstrated the effectiveness of area wide management of insects both as pests and virus vectors. Local research has provided valuable information on the use of biological control agents to control virus vectors, levels of insecticide resistance within vector populations and how vectors move within the landscape. This local knowledge combined with that from overseas researchers provides an excellent basis to attempt area wide management of viruses in the Bowen region. The first phase of this work is to generate base line data on the distribution and prevalence of the viruses and the vectors in early, mid and late season. Results from these surveys will be presented and includes the prevalence of TYLCV, PLRV and TSWV within crops across the district. The presentation will also include the prevalence of SLW within crops across the district and the proportion of those populations which are identified as TYLCV positive vectors. This phase of work also includes investigation of alternative hosts for TYLCV and PLRV, including both weed species and other crops. The cotton industry periodically experiences outbreaks of Cotton bunchy top disease (CBT) which is also caused by a polerovirus. Although CBT is present in most cotton crops each season, large outbreaks of the disease are rare. Similarly, PLRV is thought to occur in many tomato growing regions but only causes significant disease in Bowen. Potential similarities in environmental conditions between outbreaks of CBT and PLRV will be discussed.

Ministry of Agriculture, Food, Forest & Fisheries, Tonga [email protected]

Plant Pathology Department, Ministry of Agriculture, Food, Forest & Fisheries Research Station, Vaini, Kingdom of Tonga

My recent Australian Youth Ambassador for Development (AYAD) assignment in the Kingdom of Tonga, as a Plant Pathologist for the Ministry of Agriculture, Food Forest and Fisheries (MAFFF), was an incredibly rewarding yet challenging role. The Kingdom of Tonga is an archipelago of over 70 islands. The largest and most densely populated island, Tongatapu, is almost half the total land area of the whole archipelago. As Tongatapu is relatively low lying (the highest elevation is 65m in the south-east) groundwater contamination issues have risen over the last few decades, due in part to the overuse of pesticides and commercial fertilizer for high value export crops. High levels of rainfall and humidity, especially between November and April, also contribute to high fungal disease incidence and severity on many crops in Tonga. Increased government interest in IPDM practices and sustainable agricultural methods has lead to multiple projects in Tonga aiding subsistence and cash crop farmers to address these issues sustainably. My presentation will focus on my experiences as a early career plant pathologist working in the challenging field of international development, as well as projects and initiatives that could be implemented in the Kingdom of Tonga.


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SESSION 1A – APPLICATION OF NEW TECHNOLOGIES

Detection of potato potyviruses in aphids caught in water and propylene glycol trap solutions

Ms Zoe-Joy Newby

The Royal Botanic Gardens and Domain Turst [email protected]

Dr Ron van Toor

Plant and Food Research [email protected] Ron van Toor , Gaynor Malloch , Brian Fenton (1)

(2)

(2)

Bioprotection Technologies, The New Zealand Institute for Plant & Food Research Limited, Lincoln, Canterbury, NZ (2) James Hutton Institute (formerly SCRI), Invergowrie, UK (1)

Yellow-bowl traps containing water-detergent are used extensively in Scotland to monitor virus risk in potatoes from aphid virus vectors, which is calculated by multiplying the number of aphids in a weekly trap catch by a virus efficiency factor specific to each species. The proportion of aphids carrying viruses can also be measured directly using molecular diagnostic techniques, but it is not known how long the nonpersistent potyviruses, potato virus A (PVA) and potato virus Y (PVY), remain detectable in water, or if they transfer in solution between aphids, thereby negating estimates of virus incidence. We compared water with a solution of 50% propylene glycol/ water (PG50), both containing 1% detergent, to support PVA and PVY detection in the aphid Myzus persicae. Virus presence was diagnosed by RT-PCR/nested PCR and the products analysed on gels. There was no change in the proportion of alatae carrying PVA and PVY from 0 to 9 days in both solutions under laboratory conditions. In the field, the proportion of alatae carrying PVY in traps containing either solution declined from 94% at 0 days to 65% after 7 days in the presence of insect bycatches. As nucleases released by the decaying insects in the by-catch may have inhibited virus detection, activated charcoal and bentonite nucleases adsorbents, were evaluated as PG50 additives. In the presence of decaying insects, all solutions were effective in preserving PVY after 7 days in the laboratory, but in a tunnel house where air temperatures exceeded 35 °C, the proportion of alatae in water carrying PVY declined to half the initial levels, and lesser amounts in the PG50 solutions, with no benefit from charcoal or bentonite. Under summer field conditions in traps refreshed weekly the proportion of aphids carrying PVA tended to decline over the 7 days in the trap solution, while the proportion of aphids carrying PVY remained similar to when they were placed in solution. On rare occasions in extremely high summer temperatures PVY appeared transmissible from PVY-carrying alatae to virus-free aphids in both solutions. However, under normal temperatures, solutions containing detergent and water or PG50 appear suitable for monitoring the incidence of potyviruses in aphids caught in yellow-bowl traps.

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Hyperspectral leaf response of plant infected with Phytophthora cinnamomi

Zoe-Joy Newby(1), Richard Murphy(2), David Guest(3), Daniel Ramp(4), Edward Liew(1) PDDU, Royal Botanic Gardens, Mrs Macquaries Rd, Sydney, 2000, Australia (2) A11 - Edgeworth David Geology, The University of Sydney, NSW 2006, Australia (3) C81 - Biomedical Building, The University of Sydney, NSW 2006, Australia (4) School of the Environment, University of Technology, Sydney,4.5.60A, Broadway, NSW, 2007, Australia (1)

Remote sensing is routinely applied within environmental management to assess vegetation health and plant productivity. Recent developments in the use of hyperspectral remote sensing (HRS) have demonstrated numerous examples of its application to quantify foliar disease in agricultural, horticultural and forestry industries. Here we report on the ability of HRS to quantify Phytophthora cinnamomi infection in plants of native Australian ecosystems in an attempt to identify a more efficient and effective method of disease identification. A glasshouse trial investigated how leaf reflectance in species with different susceptibilities to P. cinnamomi changed in response to infection, and if this change could be distinguished from changes caused by a lack of water. Leaf reflectance in the wavelength region of 350-2500nm was measured fortnightly using a hand held spectroradiometer over four months. Data were imported into ENVI, spectra were smoothed and the first and second derivative spectra were calculated. Water features were identified within the spectra and the effect of inoculation and water stress on their size was assessed using ANOVA. A number of vegetation indices (VIs) which assess changes in leaf pigments, water content and general plant health were calculated and again analysed using ANOVA. Reflectance in the UV-NIR region (350-900nm) was assessed using principal component analysis (PCA). Infection could be identified in the water features although the response between species was not universal. A unique combination of two to three VIs could be used to identify infection in most species and these typically included reflectance in the green (530-550nm) and red regions (650-680nm), and the anthocyanin reflective index. The PCA showed treatment separation of the first derivative data within the visible and NIR region and explained more than 95% of the data variation in three components. Unique spectral signatures outside the visible range (400-700nm) were identified in two of the species suggesting the detection of P. cinnamomi infection is possible in asymptomatic species or before visually symptoms are evident when using HRS. Disease detection was more difficult in the field resistant species and once water stress became severe, changes in reflectance due to infection were often no longer significantly different from controls. If the response of individual species to P. cinnamomi infection is understood, real-time and presymptomatic disease detection may be possible with HRS. This has implications on greatly improving disease management decision making.


SESSION 1A – APPLICATION OF NEW TECHNOLOGIES

Citizen science and a smartphone application to monitor the incidence and severity of Quambalaria diseases in Western Australian marri Corymbia calophylla Cielito Marbus

Murdoch University [email protected] Cielito Marbus(1), Treena Burgess(1), Trudy Paap(1), Briony Williams(1), Pieter Poot(2), Erik Veneklaas(2), Giles Hardy(1) State Centre of Excellence for Climate Change, Woodland and Forest Health, School of Veterinary and Life Sciences, Murdoch University, Murdoch, 6150, Western Australia, (2) School of Plant Biology, University of Western Australia, Crawley, 6009, Western Australia (1)

The incidence and severity of cankers caused by Quambalaria coyrecup and Q.piterika, the cause of shoot, flower and fruit blight in marri (Corymbia calophylla), have increased significantly since the early 1990s in the south-west of Western Australia. Marri is an iconic overstorey forest tree with an extensive range in a number of diverse forest ecosystems. It plays a major role as a food source, habitat tree and refugium for numerous vertebrate and invertebrate fauna including the endangered Carnaby’s cockatoo (Calyptorhynchus latirostris), as well as being a key species providing pollen and nectar for apiarists. Consequently, the impact of these pathogens on marri is causing increasing concern across the community for a wide range of reasons. We have developed a smartphone marri application that works across Android and IPhone mobile platforms that can be used by interested members of the public, local government agencies, foresters and scientists to capture location (GPS), incidence and severity of cankers and shoot blight on trees, and lodge photographs and other critical site information to a central server. To fully inform users, the smartphone marri application also supplies detailed photographic information and text on what cankers and shoot blight look like at different stages of development, and how to differentiate these from other similar biotic and abiotic symptoms. Importantly, it also provides information on how to establish and monitor fungicide and other treatment trials that will be statistically robust and informative for scientific purposes across the marri range. The development and use of the ‘marri app’, together with the strengths and weaknesses associated with using citizen science to help drive research will be discussed.

Field evaluation of a bioherbicide for control of parkinsonia (Parkinsonia aculeata) in Australia Dr Victor Galea

The University of Queensland [email protected] Victor Galea, Ken Goulter, School of Agriculture and Food Sciences, The University of Queensland, Gatton, QLD 4343 Australia

Parkinsonia Parkinsonia aculeata L., is a serious weed of Australia’s rangelands affecting more than 3.3 million ha with the potential to invade 70% of the mainland (March 2009). This highly invasive thorny weed is a major impediment to cattle production and a threat to wetlands. A bank of fungal isolates from dieback affected parkinsonia collected across northern Australia has been evaluated under laboratory and glasshouse conditions to select isolates aggressive against this woody weed host. A selection of isolates drawn from fungal genera including Lasiodiplodia, Macrophomina and Neoscytalidium showed great promise as potential bioherbicides and are currently undergoing commercial development. A field experiment was established among naturally occurring parkinsonia on Stradbroke Station (near Duchess, western Queensland) to evaluate the performance of three isolates singly, or combined together in their ability to cause infection and subsequent mortality in adult trees. Isolates were formulated into gelatine capsules as individual isolates or as a blend (equal parts) of all three. Control capsules contained sterile carrier media only. Trees were inoculated in April 2011 by introducing single capsules into 10 mm diameter holes drilled into the stem (30 mm depth) at 200 mm above ground level. Inoculation holes were sealed with domestic roof & gutter silicone sealant. Trial assessments conducted at six monthly intervals over a 2 year period assessed plants for attributes such as inoculation success, presence of stem lesions and or discolouration, and degree of overall tree morbidity / mortality expressed as the proportion of canopy showing dieback. First signs of infection became obvious at the 12 month assessment as evidenced by branchlet death and general morbidity across all fungal treatments. At the 18 month assessment, all fungal treatments demonstrated signs of significant dieback symptoms including stem discolouration, major branch death, and in some cases main stem death. There was little evidence of further progression of dieback at the 24 month assessment. The outcomes of this trial clearly demonstrates the viability of this (patented) inoculation method to initiate a dieback event among naturally growing parkinsonia trees and shows great promise as an additional tool to employ in the management of woody weeds.


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SESSION 1B – APPLICATION OF NEW TECHNOLOGIES

Can a single genomic difference result in a better biocontrol agent? Ms Claudia Lange

Bio-Protection Research Centre, Lincoln University [email protected] Claudia Lange(1) , Richard Weld(2) , Murray Cox(1)(3) , Rosie Bradshaw(1)(3) , Alison Stewart(4) , Johanna Steyaert(1) Bio-Protection Research Centre, Lincoln University, PO Box 85084, Lincoln 7647, New Zealand (2) Lincoln Agritech Ltd, PO Box 69133, Lincoln 7640, New Zealand (3) Institute of Fundamental Sciences, Massey University, Palmerston North 4442, New Zealand (4) Marrone Bio Innovations, 2121 Second St, Davis, California 95618, USA (1)

The filamentous fungus Trichoderma atroviride is used widely for biological control of major plant diseases. Biocontrol activity is linked to a wide range of parameters and we have limited knowledge of what specific attributes make certain strains particularly effective as a biocontrol agent (BCA). In this study, we report on molecular differences between two closely related T. atroviride isolates and the implications they might have on biocontrol activity. Two T. atroviride isolates (LU132 and LU140) were isolated from the same onion paddock in New Zealand as potential BCAs against onion white rot. The isolates were phenotypically distinct and extensive studies found that LU132 was an excellent BCA and achieved better control than LU140 of a variety of plant pathogens. Direct comparison of a wide range of phenotypic characteristics of the two isolates found that the biggest difference between the isolates is LU132’s faster growth rate. Attempts were made to design an isolatespecific molecular marker for LU132, but it was impossible to distinguish it from LU140, suggesting high genetic similarity. Sequencing of the genomes of both isolates revealed only 2 single nucleotide polymorphisms (SNPs). The SNPs were associated with 3 genes similar to: 1) a hypothetical gene, conserved in fungi; 2) predicted Small EDRK-rich Factor H4F5 (SERF), conserved in animals and fungi; 3) Proliferating Cell Nuclear Antigen (PCNA), conserved in eukaryotes and archaea. No expression differences of these 3 genes could be identified but cDNA sequencing revealed a gene annotation error in SERF. While the published annotated genome of T. atroviride describes SERF as having 2 exons and one intron, it actually has an additional exon in LU132 and LU140. One of the SNPs is located in the 3rd exon of SERF where it changes the amino acid sequence in LU132. Bioinformatic analysis suggests that the amino acid change creates a MAPK docking motif on the LU132 SERF protein that is not present in the LU140 protein. To study the function of the gene it was knocked-out in both isolates via Agrobacterium-mediated transformation and the mutants were subjected to phenotypic examinations. We will present first results from the gene function analysis and discuss potential implications for biocontrol activity in this important species.

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Application of viability PCR for the selection detection of live pathogens in a quarantine setting Mr Robert Taylor

Ministry for Primary Industries [email protected] Robert Taylor (1), Stephanie FitzGerald (1), Suzanne Keeling (2), Brett Alexander (1) (1)

(2)

Plant Health and Environment Laboratory, Ministry for Primary Industries, PO Box 2095, Auckland, New Zealand Science and Risk Assessment, Ministry for Primary Industries, PO Box 2526, Wellington, New Zealand

Molecular diagnostics utilising polymerase chain reaction (PCR) techniques are now routinely used for the detection and identification of regulated organisms in quarantine and biosecurity. However, one limitation of PCR technology has been the inability to differentiate positive results originating from live or dead cells. Correlating positive PCR results with diseased crops can be relatively straightforward. However, interpreting the biological risks of PCR positives in asymptomatic nursery stock, pollen, fresh produce and other environmental items can be very difficult. Biosecurity decision makers are faced with the challenge of balancing PCR positive results with the time needed to demonstrate viability of the organism, assuming it can be grown using traditional culturing techniques. One recent approach to address this problem has been the use of nucleic acid intercalating dyes, such as propidium monoazide (PMA) and ethidium monoazide (EMA), prior to DNA extraction to selectively inhibit the PCR amplification of DNA derived from dead cells. PMA and EMA are unable to penetrate viable cells with intact membranes but will penetrate dead cells with compromised membranes. Exposure to light allows cross-linking of these dyes to DNA which inhibits PCR amplification. In this study we assessed the applicability of such an approach by using PMA or EMA in conjunction with existing real-time PCR assays to detect viable cells of biosecurity risk organisms. The development, application and some of the practical limitations of this technology to detect viable pathogen cells in a quarantine setting are discussed.


SESSION 1B – APPLICATION OF NEW TECHNOLOGIES

The detection of brassica-infecting viruses in the aphids Myzus persicae and Brevicoryne brassicae

Preliminary results on the use of electronic nose for the early diagnosis of bacterial canker of kiwifruit

Ms Sarah Thompson

Dr Francesco Spinelli

The New Zealand Institute for Plant and Food Research Ltd [email protected] Sarah Thompson, Sandi Keenan, John Fletcher, David Teulon, Simon Bulman The New Zealand Institute for Plant and Food Research Ltd, Lincoln, New Zealand

Viruses can significantly reduce brassica crop yield and quality. They are vectored between crops by sap-sucking insects – the key vectors in New Zealand being the aphids Myzus persicae and Brevicoryne brassicae. Monitoring the presence of the aphid vectors is currently seen as the major determinant for virus risk and can lead to spraying regardless of actual virus presence. Aphid monitoring is often carried out by attracting flying aphids to yellow bowl traps (YBTs) containing a trapping solution. The aim of this study was to develop techniques to directly monitor viruses in field captured aphids to aid farmers in decision-making about risk to crop. qPCR assays based on coat protein gene were developed for Turnip mosaic virus (TuMV) and Turnip yellows virus (TuYV). An internal control assay based on the elongation factor 1α gene was also designed for detecting the aphids M. persicae and B. brassicae. Propylene glycol (PG) is a candidate medium for trapping insects while at the same time preserving nucleic acids. Virus-carrying M. persicae were stored in PG for up to four weeks with individuals insects removed and tested weekly for virus levels. Both viruses could still be detected in the aphids after four weeks of storage in PG although TuMV was nearing the limit of detection; levels of TuYV were always substantially greater than for TuMV. TuMV is a stylet-borne Potyvirus and had a substantially lower titre in fresh aphids than the persistent, circulative Luteovirus TuYV. To test whether these qPCR tests translated to field conditions, virus-carrying aphids were spiked into yellow bowl traps and incubated under field conditions for up to 2 weeks. Virus could still be detected in these aphids after this period. Subsequently, individual wild aphids flying in rape fields were screened for TuYV and TuMV. It was demonstrated that both viruses could be detected in wild aphids caught in YBTs. PG, a relatively cheap and non-toxic medium, was confirmed to be effective at preserving aphids in YBT’s for testing of virus load. In time, such detection and quantification of viruses in insects could become a semiautomated process allowing relatively cheap monitoring of virus levels in the field. This would allow farmers to make informed decisions about spraying regimes, thus reducing costs.

Department of Agricultural Sciences, Alma Mater Studiorum - University of Bologna [email protected] Francesco Spinelli(1), Antonio Cellini(1), Giampaolo Buriani(1) , Irene Donati(1), Valentino Giacomuzzi(2) , Maria Teresa Rodriguez-Estrada(3) , Stefano Savioli(3) , Brian Farneti(1), Franco Biasioli(4) , Simona Cristescu(5), Guglielmo Costa(1), Joel Vanneste(6) Department of Agricultural Sciences, Alma Mater Studiorum -University of Bologna, viale Fanin 46, 40127 Bologna - Italy (2) Faculty of Science and Technology, Free University of Bolzano, piazza Università 5, 39100 Bolzano - Italy (3) Department of Food Science and Technology, Alma Mater Studiorum -University of Bologna, viale Fanin 40, 40127 Bologna - Italy (4) Food Quality and Nutrition Department, Research and Innovation Centre - Fondazione Edmund Mach, Via E. Mach 1, 38010 S. Michele all’Adige (TN)- Italy (5) Radboud University, Institute of Molecules and Materials, Heyendaalseweg 135, 6525AJ Nijmegen - The Netherlands (6) Plant & Food Research, Ruakura, Private Bag 3123, Waikato Mail Centre, Hamilton, 3240 - New Zealand (1)

One of the major constrain in plant disease diagnosis is the sampling procedure that needs to be carefully designed to detect reliably the presence of a pathogen. Therefore, even thought DNA-based protocols are the golden standard for the diagnosis, they may produce false negative results if the sampled material is not contaminated. On the other hand, volatiles-based diagnosis can be performed on the whole plant thus minimizing the risk of false negative. Nowadays, techniques such as gas chromatography-mass spectroscopy (GC-MS) and proton-transfer time of flight mass spectroscopy (PTR-TOF-MS) constitute a powerful method to characterize volatiles emitted by infected plants and to identify possible disease-specific markers. However, these techniques are very expensive, time-consuming and require trained personnel. Electronic nose may represent a sensitive, accurate and operator-friendly alternative for rapid and reliable screening of volatiles produced by asymptomatic infected plants. In the present study, the analysis of volatile compounds is used for the diagnosis of bacterial canker of kiwifruit (Pseudomonas syringae pv. actinidiae) on propagation material. The profile of volatiles emission was initially performed by GC-MS and PTRTOF-MS. In addition, two different electronic noses, EOS507 (Sacmi Scrl, Imola, Italy) and PEN3 (Airsense Analytics GmbH, Schwering, Germany), both based on metal oxide semiconductors, were used for diagnosis. The results show that electronic-nose might be adapted to be used in practical conditions, such as nurseries or customs, to screen large quantity of asymptomatic plant material in order precisely steer molecular diagnosis.


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SESSION 2A – BIOLOGICAL INTERACTIONS AND PLANT DISEASES

What makes Trichoderma rhizosphere competent: A molecular analysis Dr Artemio Mendoza Mendoza Bio-Protection Research Centre [email protected]

Johanna Steyaert(1), Damian Bienkowski(1), Jessica Yardley(1), Mark Braithwaite(1), Kirstin McLean(1), Alison Stewart(2), Artemio MendozaMendoza(1) Bio-Protection Research Centre, PO Box 85084, Lincoln University, Lincoln 7647 (2) Marrone Bio Innovations, 2121 Second St, Davis, California 95618, USA (1)

Establishment of root symbiosis has been reported as one of the key drivers of biocontrol success for members of the fungal genus Trichoderma. This root symbiosis is described as a two-step process, whereby Trichoderma isolates colonise the soil surrounding the root (rhizosphere) and then penetrate the root tissue and establish an endophytic relationship. The ability to colonise and then proliferate over time within the rhizosphere is termed rhizosphere competence, and there have been numerous reports of Trichoderma biocontrol strains which persist within the rhizosphere over the growing season of the crop plant. In this study, we are exploring the genetic basis of rhizosphere competency in Trichoderma atroviride LU132, which is a commercial biocontrol agent. Analysis of the transcriptome of LU132 proliferating in the rhizosphere of maize revealed a major down-regulation of genes when compared with Trichoderma free-living in soil. These findings are currently being explored through over-expression of selected genes and assessment of presence and proliferation of mutants within the rhizosphere. Analysis of nucleic acids from soil samples can be time consuming and not necessary amenable to large scale trials, therefore we are analysing the validity of using a root exudate assay from both maize and wheat plants to generate rhizosphere transcriptomes from Trichoderma. Results from these experiments will be discussed.

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Species- and strain- specific identification and quantification of root disease suppressive Trichoderma inoculants in cropping soils Dr Belinda Stummer CSIRO [email protected]

Belinda Stummer(1), Qingxia Zhang(2) , Rosemary Warren(1) , Hetong Yang(3), Paul Harvey(1)(3) CSIRO Ecosystem Sciences, Waite Campus, PMB 2 Glen Osmond, 5064, South Australia (2) College of Horticulture and Plant Protection, Yangzhou University, Yangzhou, 225009, Jiangsu, China (3) Biology Research Institute, Shandong Academy of Sciences, Jinan, 250014, Shandong, China (1)

Inoculation of wheat and barley field trials in southern Australia with Trichoderma harzianum (Tr904, LTR-2) and T. koningiopsis (Tr905) have significantly suppressed (P < 0.05) root disease severity caused by Rhizoctonia solani and Pythium irregulare. The aim of this study was to develop Trichoderma speciesand strain- specific quantitative assays (qPCR) to define the rhizosphere dynamics and soil persistence of these disease suppressive inoculants. Primers for Trichoderma qPCR were designed from the internal transcribed spacer region of the 5.8S rDNA (ITS-5.8s rDNA) and sequences of DNA fragments (AFLP) diagnostic for each inoculant. The minimum detection threshold (MDT) of each qPCR assay was determined via inoculation (102 – 108) and recovery (microbiology) in 2 contrasting soils; an alkaline sand (pH 8.9, Warramboo, SA) and an acidic loam (pH 6.0, Temora, NSW). Trichoderma were quantified (microbiology and qPCR) immediately after inoculation (T0) and at 28 (T28) days. MDT’s of the qPCR assays varied between 104 (LTR-2) and 105 (Tr905) conidia per gram of soil (c g-1 soil), with the maximum detected being 108) c g-1 soil. Both the minimum and maximum qPCR DT’s were independent of soil type. At Trichoderma inoculum levels above the qPCR MDT’s, there was a strong correlation (r2 = 0.969) between culture dependent (microbiology) and independent (qPCR) quantification methods. Significant differences (P < 0.001) in soil colonisation and persistence (microbiology, qPCR) were observed between species of Trichoderma inoculants over a 56 day incubation period. In acid and alkaline soils, Trichoderma harzianum LTR-2 and Tr904 increased 100 fold (from 105 – 107 by T28 and maintained these levels for the remainder of the experiment. T. koningiopsisTr905 however, increased 30 fold (to 3 x 106 c g-1 soil) in both soils by T28, but only continued to proliferate in the acidic soil, reaching 107 c g-1 by T56. There was no significant change in Tr905 inoculum in alkaline soil between T28 and T56. In controlled environment wheat bioassays (acidic loam soil) by T28 post-emergence (tillering), all 3 inoculants actively colonised rhizosphere and bulk soils to a depth of 20cm. Root colonisation was however, restricted to 0-10 cm. By T56 (late anthesis), Tr904 and LTR-2 root and soil inoculum had persisted, whereas those of Tr905 were below the qPCR MDT. In summary, these Trichoderma qPCR assays can be applied to monitor rhizoshere competence of inoculants and their roles in suppression of root diseases.


SESSION 2A – BIOLOGICAL INTERACTIONS AND PLANT DISEASES

Dissecting the molecular crosstalk between endophytic fungi and their host plants: Trichoderma as fungal model system Dr Artemio Mendoza Mendoza Bio-Protection Research Centre [email protected]

Mendoza-Mendoza A(1), Lawry R(1), Nieto-Jacobo M.F(1) , Brown C(2) , Salazar-Badillo F(1)(3) , Greenwood D(4) , Schnable P(5) , Braithwaite M(1) , Jimenez-Bremont JF(3), Alison Stewart(6) Bio-Protection Research Centre, P.O. Box 84, Lincoln University, Canterbury, New Zealand (2) Biochemistry Department and Genetics, University of Otago P.O. Box 56, 710 Cumberland St, Dunedin 9054, New Zealand (3) Institute for Scientific and Technological Research of San Luis Potosi, IPICYT. Camino a la Presa San José 2055, Lomas 4 sección. Zip. 78216. San Luis Potosí, México (4) School of Biological Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand (5) 2025 Roy J. Carver Co-Laboratory, Iowa State University, Ames, Iowa 50011-3650. USA (6) Marrone Bio Innovations, 2121 Second St, Davis, California 95618, USA

Identification of a naturally occurring, mild isolate of Tamarillo mosaic virus Mr Arnaud Blouin

The New Zealand Institute for Plant & Food Research Limited [email protected] Katrin Pechinger(1), Arnaud G Blouin(1), Samantha J Edwards(1), Kar M Chooi(1), Daniel Cohen(1), Robin M MacDiarmid(1)(2) Plant & Food Research Mt Albert, Private Bag 92169, Auckland, 1142, New Zealand (2) School of Biological Sciences, The University of Auckland, PO Box 92019, Auckland 1142, New Zealand (1)

(1)

Symbioses, including fungal endophytes in plants, are one of the most remarkable interactions in nature. Endophytes improve plant growth, disease resistance, nutrient availability and abiotic stress tolerance, while the fungi themselves obtain nutrients. Despite directly benefiting from this symbiosis, plants still react to colonization from endophytes by activating their innate immune system which has evolved to recognize common features of microorganisms, termed microbe-associated molecular patterns (MAMPs). Plants translate this recognition into a defence response that is specifically directed against the invader encountered. Trichoderma spp. are soil-borne filamentous fungi which enter the roots of higher plants and form symbiotic relationships (endophytism). The relationship between endophytes and their respective hosts requires constant communication between the organisms involved. For example, the fungal-derived phytohormone indole acetic acid (IAA) plays an important role in cross-communication between Trichoderma and Arabidopsis thaliana. However, we have shown that IAA derivatives are a complex mixture of molecules which are isolate dependent. Interestingly, we show no correlation between IAA/IAA-derivatives production and root promotion in A. thaliana. This finding suggests that additional, currently unknown molecular signals may be even more important in the interaction between Trichoderma and plants. A comprehensive knowledge of the gene expression changes in both the fungus and the plant is required. Using Hi-Throughput RNA-Seq technology, we analysed the transcriptomes of maize and Trichoderma during T. virens root colonization. Our results suggest that diverse signalling cascades related to plant immunity are differentially regulated in the plant colonization. Additionally, we found that of 50 fungal transcripts encoding secreted proteins at 3, 5 and 7 days of interaction were upregulated. An additional 103 transcripts encoding for secreted proteins were upregulated at only the 3 day time point. Our current work is focused on the functional characterization of these proteins and their relationship to plant colonization. A compressive analysis of our findings will be discussed in this conference.

Tamarillo mosaic virus (TamMV, Potyvirus), a tamarillo isolate of Potato virus A (PVA), is the most damaging virus that infects tamarillo, resulting in low plant vigour, poor yield and discolouration of fruit. Most orchards grown in New Zealand are infected with the virus. In this study a branch of a TamMVinfected tree that bore leaves and fruit that had no or few virus symptoms was identified in a commercial orchard; the branch tested positive for potyvirus infection by ELISA. The rest of the plant was showing typical symptoms of the virus. This plant, named LL, was the core of this research. Three tamarillo genotypes were screened with two virus isolates in order to identify differences in susceptibility to virus infection. The tamarillo genotypes selected were the seedling from the LL plant, cuttings from a tamarillo labelled #23 and selected from a different commercial orchard for its apparent resistance to the virus (#23 being the only non infected plant present in a block over a period of 6 years), and Mulligan Round, a commercial cultivar known to be susceptible to the virus. The two virus isolates selected were LL6 from the symptomless branch of the LL tamarillo and B14, from a plant showing strong symptoms typical of the virus. When infected with the B14 TamMV strain, the three tamarillo genotypes were found to be susceptible, demonstrating that the genotype of the tamarillo plant did not confer resistance to TamMV. The infection rate was comparable between the genotypes and most plants expressed typical TamMV symptoms. When infected with the LL6 virus isolate, most replicates of all the tamarillo genotypes were symptomless, only giving mild symptoms to less than 5% of the infected plants. Information from deep-sequencing of the genome sequences of both the mild and severe isolates will be presented. The mild strain of TamMV is closely related to previously published sequences of TamMV and PVA but has at least some differences in the HC-Pro suppressor of silencing gene. The discovery of this naturally occurring, mild isolate of TamMV was made possible by the close working relationship between orchardists and scientists. Please refer to Samantha Edwards’ poster for an update on the ability of the mild isolate of TamMV to cross-protect against severe isolates.


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SESSION 2B – BIOLOGICAL INTERACTIONS AND PLANT DISEASES

Incidence of Tomato Leaf Curl Virus (ToLCV) in the Philippines and Development of an Infectious DNA Clone for Virus Resistance Screening in Tomato

Wafaa Haggag

Ms Lolita Dolores

University of the Philippines Los Banos (UPLB) [email protected] Lolita Dolores(1), Shamdee Nahar(1), Araceli Alcachupas(1), Hayde Galvez(1), Melquiades Reyes(1), Alma Canama(1) (1)

Crop Science Cluster, Institute of Plant Breeding, College of Agriculture,University of the Philippines Los Banos, College, Laguna, Philippines

Survey and collection of virus infected tomato was done primarily, to determine the incidence and distribution of the Philippine tomato leaf curl virus (ToLCV-P), a whitefly transmitted begomovirus. Tomato samples with and without virus symptoms were collected and subjected to ELISA and PCR for virus detection. The tomato leaf curl Philippine virus (ToLCV-P) was found to be the most predominating virus with an incidence of 82%. The other viruses that were detected included TMV, CMV and ToMV in decreasing order of virus incidence. Majority of the samples came from plants with multiple virus infections exhibiting varying symptoms of mosaic, mottle, leaf curl, leaf distortion, leaf clustering, yellowing and stunting while some samples came from plants with mild or apparently healthy appearance. Most of the representative symptomatic samples collected from the different regions were found positive for ToLCV generating a 1.1kB DNA fragment with ToLCV specific primers. A total of 50 ToLCV virus isolates were obtained and are being characterized. Meanwhile, the full length DNA-A of ToLCV – Laguna isolate was cloned and inserted into a Ti plasmid vector and made infectious through Agrobacterium- mediated inoculation. A. tumefaciens LBA 4404 was used to agroinoculate healthy seedlings of tomato with bacterial suspension harboring the ToLCV –DNA-A using a syringe needle, made to penetrate the base of the stem and the whole plant with at least ten injections. Symptoms of chlorotic spots and leaf curling were observed 2 weeks after inoculation. The efficacy of this technique in ToLCV resistance screening in tomato and its practical application in breeding for resistance is also discussed.

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Optimization, formulation and stabilisation of the biocontrol yeast Rhodotorula glutinis for controlling strawberry blight

National Research Centre [email protected] Wafaa M. Haggag (1) , Fareed Abd El-Kreem(2) Dep

artment of Plant Pathology, National Research Centre , Dokki, Egypt

Biocontrol agents represent an alternative or supplement to chemicals for disease control. Rhodotorula glutinis was evaluated for its activity in reducing gray mold and blight diseases of strawberry caused by Botrytis cinerea and Phomopsis obscurans , respectively in vitro and in vivo. Spore germination of pathogens in PDB was greatly controlled in the presence of living cell suspensions In order to standardize the mass and metabolite production some cultural conditions like different incubation time in hours, pH, carbon sources and concentrations and nitrogen source were determined. Yeast was produced biopolymers (Polysaccharide-peptide mixture) when grown in a medium with excess fructose as carbon source and soybean as nitrogen source . The stabilization techniques were have evaluated using liquid formulations. Preharvest application of liquid formulation of certain microbial isolates provided an effective control of leaves blight as well as fruit gray mould disease pre and protect fruit during storage than the tested fungicide at the recommended levels.


SESSION 2B – BIOLOGICAL INTERACTIONS AND PLANT DISEASES

Germination and bioactivity of Trichoderma atroviride affected by culturing and storage conditions

Effect of Aureobasidium isolates on mycelium growth of three major bunch rot pathogens of grapes

Mr Amir Daryaei

Ms Sujeewa Rathnayake

Amir Daryaei(1), Richard E Falloon(1), Travis R Glare(1), Eirian Jones(1), Hossein Alizadeh(1), Alison Stewart(2)

RM Sujeewa P Rathnayake, Sandra Savocchia , Leigh M Schmidtke , Christopher C Steel

Bio-Protection Research Centre, Lincoln University, Lincoln 7647, Canterbury, New Zealand Marrone Bio Innovations, Davis, California 95618, USA

National Wine and Grape Industry Centre, School of Agricultural and Wine Sciences, Charles Sturt University, Wagga Wagga, NSW 2678

Bio-Protection Research Centre [email protected]

(1)

(2)

Identification of the production and storage factors that affect conidial germination and bioactivity (fitness) will assist the success of biological control agents. Effects of culturing conditions on conidial fitness of Trichoderma atroviride LU132 were examined in different storage conditions over time. Abiotic factors (temperature, nutrients, water activity, pH) during production were studied. Conidia from the culturing regimes which resulted in greatest and least bioactivity against Rhizoctonia solani in dual culture were selected to assess effects of storage condition on conidial fitness. Fitness of the test conidia was examined after storage at 30°C and at 0 or 50% relative humidity (RH) over 6 months. Fitness declined over time, and the decline was greater for 50% RH than 0% RH. The greatest number of conidia and germination percentage resulted from conidia produced at 25°C, but greatest bioactivity resulted from those produced at 30°C. Different C to N ratios (5:1 or 160:1) did not affect these parameters. However, fewer conidia were produced at 30°C, and the least germination and bioactivity resulted from conidia produced at 20°C. Conidia can be divided into two groups: those adapted to extreme culturing conditions (e.g. high temperature), and those protected by nutrients during storage. However, environmental factors are not independent. For example, conidial production at 30°C is probably accompanied by water stress, oxidation, and rapid pH change which may also affect fitness.

Charles Sturt University [email protected]

Currently, fungicide treatments represent the primary method for the control of bunch rot disease of grapes. But chemical control methods have consequences with social and environmental perspectives. Public concerns about fungicidal residues in grapes and development of fungicidal resistant strains of the pathogens have promoted the search for alternative means, less harmful to environment and human health. Recently, considerable success has been achieved by utilizing the microbial antagonists to control post and pre-harvest diseases of fruits. Aureobasidium pullulans, an important cosmopolitan yeast-like fungus, colonize on the surfaces of many fruits and vegetable is a potential biocontrol agent for plant pathogens. In this experiment, different Aureobasidium isolates were isolated from surfaces of Chardonnay grapes collected from four different berry development stages during 2012 vintage. Altogether 27 Aureobasidium isolates were screened against the three major bunch rot pathogens of grapes such as Botrytis cinerea, Colletotrichum acutatum and Greeneria uvicola under in-vitro condition. According to the results, Aureobasidium isolates showed high level of suppression on mycelium growth of the fungus Greeneria uvicola when compared to the other tested two pathogens Colletotrichum acutatum and B.cinerea.


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SESSION 2C – BIOLOGICAL INTERACTIONS AND PLANT DISEASES

Trichoderma koningiopsis (Tr905) suppression of a barley root disease complex alters the species composition and intraspecific genetic structure of pathogen populations

Prof Michael Pearson The University of Auckland [email protected]

Rosemary Warren

Michael Pearson

CSIRO [email protected] Rosemary Warren(1) , Jingli Yu(2) , Belinda Stummer(1) , Li Jinhua(3) , Xiuyun Lu(4) , Paul Harvey(1) CSIRO Ecosystem Sciences, Waite Campus, PMB 2 Glen Osmond 5064, South Australia (2) College of Environment and Resources, Inner Mongolia University, Hohot 225009, Inner Mongolia, China (3) Bio-protection Research Centre, Lincoln University PO Box 85084 Lincoln 7647 Canterbury New Zealand (4) Institute of Plant Protection, Hebei Academy of Agricultural and Forestry Sciences, Baoding, Hebei 071000, China (1)

Patches of poor barley growth, characteristic of Pythium and Rhizoctonia root rot, were observed in disease suppressive inoculant field trials at Urania and Bute in South Australia. At 12 weeks post-emergence, plots inoculated with Trichoderma koningiopsis Tr905 were observed to have improved crop growth, compared to the uninoculated plots. The aims of this study were to determine i) the incidence of a PythiumRhizoctonia root disease complex at the 2 trial sites; ii) the root disease suppressive efficacies of T. koningiopsis Tr905 and iii) the relationships between Tr905-induced disease suppression and the genetic structure of pathogen populations. Pathogen root isolation frequencies were used to quantify disease incidence and Tr905 disease suppression, the latter also including changes in soil-borne pathogen inoculum. Taxonomic identities of isolates were determined by morphology and species-specific PCR. At Urania, Pythium disease incidence (66 %) was significantly greater than Rhizoctonia (8 %). Incidences of Pythium and Rhizoctonia at Bute were 78 % and 27 % respectively. Tr905 significantly reduced root disease incidence of Rhizoctonia (Bute -50 %) and P. irregulare (Bute -33 %, Urania -24 %). Inoculant-induced suppression of root disease and rhizosphere inoculum was comparable to or better than that achieved with the chemical seed treatment (difenconazole + metalaxyl-M). AFLP analyses resolved significant genetic differentiation between geographical (Bute vs Urania) populations of Rhizoctonia and P. irregulare. Significant intraspecific genetic differentiation between untreated and Tr905treated populations of these pathogens was also observed at both trial sites. This was most evident in the Rhizoctonia disease complex at Urania, where the taxonomic compositions of untreated and Tr905-treated pathogen populations were dominated by R. oryzae and R. solani AG-8 genotypes, respectively. Genetic differentiation was also observed at Urania between P. irregulare and Rhizoctonia populations isolated from inside and outside of disease patches.. In summary, Tr905 significantly decreased the frequency of Rhizoctonia and Pythium root infection, resulting in disease suppression and significant shifts in the genetic structure of the pathogen populations.

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Why mycologists should be interested in viruses: The interaction and effects of mycoviruses on their fungal hosts.

School of Biological Sciences,The University of Auckland, Private Bag 92019,Auckland, New Zealand

Until relatively recently the mycovirus literature was dominated by reports of dsRNA viruses, either unencapsidated or with isometric particles, however it is becoming increasingly evident that there is a far greater variety of mycoviruses than previously thought. The predominant view of viruses, in general, is that as obligate parasites they have a negative affect on their hosts. For mycoviruses it is clear that this view is too simplistic and their effects on their fungal hosts can range from clearly detrimental through symptomless to advantageous. In addition the effects on the fungal host may have either positive of negative flow on effects on crop production depending upon the role of the fungus in the crop ecosystem. For example the fungus may be a plant pathogen, such as Botrytis or Sclerotinia, or an introduced biological control such as the entomopathogenic fungus Beauveria. While in most cases the effects of the viruses on in-vitro growth of their fungal host are small, results from Botrytis viruses have produced conflicting results from in-vitro growth assays and pathogenicity assays on plants. In addition we have observed substantial differences between the effects of viruses on different B. cinerea isolates. Since hyphal anastomosis is the only known mechanism of horizontal transmission of mycoviruses, vegetative incompatibility is often assumed to be a barrier to mycovirus spread. However, indirect evidence from the distribution and genetic variability of Botrytis mycoviruses and direct experimental evidence of spread between incompatible fungal isolates of other fungi is challenging this assumption.



Seasonal and regional variation of Botrytis in New Zealand vineyards Dr Peter Johnston

Landcare Research [email protected] Peter Johnston, Paula Wilkie, Karyn Hoksbergen, Duckchul Park Landcare Research, Private Bag 92170, Auckland, New Zealand

Genetic diversity of Botrytis in New Zealand vineyards was surveyed over the period 2008 to 2012 from five wine growing regions. Isolates were gathered from symptomless flower buds immediately prior to flowering and, from the same vines, from diseased fruit at harvest. The isolates collected in spring represent the total genetic diversity of Botrytis associated with fruit in the vineyard, whereas the isolates collected in autumn comprise only that part of the Botrytis population that is associated with disease at harvest. Both B. cinerea and B. pseudocinerea were present, with B. cinerea being the most common species. Within B. cinerea, isolates containing both the Flipper and Boty transposons were more common than those with only one transposon, or with neither. Despite the fact that Botrytis produces huge numbers of air-borne spores, strong geographic structure to the New Zealand vineyard population was detected. B. pseudocinerea was common in the two Auckland vineyards sampled but infrequent elsewhere. Within B. cinerea, isolates containing only the Flipper transposon were more common in the Auckland region than elsewhere; isolates containing only the Boty transposon were more common in the Waipara region than elsewhere. There was also strong seasonal variation in the vineyard Botrytis diversity. Even in those vineyards where B. pseudocinerea, Boty-only and Flipperonly isolates were common at flowering, they were rarely detected in association with diseased fruit at harvest. These observations suggest that B. pseudocinerea, and isolates with one or both of the Flipper and Boty transposons missing, are less capable of causing disease than B. cinerea or isolates with both transposons present. Results wil be presentred from pathogenicity tests carried out to test this explanation.

Biological interactions of mites and microbes associated with gall formation in Scotch Broom Cytisus scoparius Dr Chantal Probst

Landcare Research [email protected] Chantal Probst(1), Nitish Anand(1), Varsha Mala(2), Daniel Than(3), ZhiQiang Zhang(1), Sarah Dodd(1), Quentin Paynter(1), Hugh Gourlay(4), Stanley Bellgard(1), Simon Fowler(4), Landcare Research, Private Bag 92170, Auckland 1142, New Zealand School of Biological Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand (3) BioDiscovery New Zealand Limited, 24 Balfour Rd, Parnell, Auckland, New Zealand (4) Landcare Research, PO Box 69040, Lincoln 7640, New Zealand (1) (2)

Originally from western and central Europe, Scotch broom (Cytisus scoparius) was introduced to New Zealand as an ornamental plant, and has become a significant weed in pastures, commercial plantations and native ecosystems. Biocontrol is being attempted using a suite of introduced arthropods including the eriophyid broom gall mite (Aceria genistae), which was first released in 2008 and originated from France. Aceria genistae causes abundant galls on broom which can lead to the death of whole branches and plants. In the absence of this biocontrol agent, smaller galls have been observed. Scanning electron microscope images of A. genistae revealed spores of unknown microbial species adhering to its integument. It has been hypothesised that a synergistic relationship between gall mites and another pathogen was responsible for the formation of extensive galls on C. scoparius. This study was designed to investigate the relationship between mites and pathogens in broom by inoculating microbial gall isolates to broom, screening microbial endophytes from New Zealand and French C. scoparius stems and galls, and determining the effects of miticide and fungicide treatments on mite and microbial populations and broom morphology. No significant differences were observed between broom seedlings inoculated with spores from microbial gall isolates and the controls, suggesting that these microorganisms were not detrimental to the plant. Morphologically distinct isolates recovered from broom tissues were identified by sequencing the ITS gene region and identifying the closest sequence match in a GenBank Blastn search. In total, 105 genetically unique endophytic fungi and 29 bacteria were isolated from broom tissues. Among the endophytic fungi, 17 belonged to the Basidiomycota and 88 to the Ascomycota phyla. Species of Phoma and Alternaria were predominantly isolated from plant tissue with 90.3 and 43.0% isolated from New Zealand plants, respectively and 91.2 and 47.1% isolated from French plants, respectively. Sequence alignments of fungal DNA from New Zealand and France showed 11 common fungal genera with 100% sequence homology, at least 7 genera specific to France and 25 to New Zealand. The results indicate an unexpected diversity of endophytes associated with an invasive plant species in its exotic range. Significantly higher gall numbers were observed on plants without miticide treatments than on those with miticide applications, with no effect in the fungicide treatments. Endophyte diversity and abundance varied with time and treatments, resulting in a complex network among the biocontrol agent, microbial endophytes and predators.


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Transcriptome analysis of the beneficial fungus Trichoderma virens during interaction with Zea mays.

Ms Alicia Greenhill

La Trobe University [email protected]

Mr Robert Lawry

Lincoln University [email protected] Robert Lawry , Maria Fernanda Nieto-Jacobo , Chris Brown , Alison Stewart(2), Artemio Mendoza-Mendoza(1) (1)

(1)

(3)

Bio-Protection Research Centre, PO Box 85084, Lincoln University, Lincoln 7647, [email protected], [email protected], [email protected] (2) Marrone Bio Innovations, 2121 Second St, Davis, California 95618, USA, ast [email protected] (3) Biochemistry Department School of Medical Sciences, University of Otago, New Zealand. [email protected] (1)

Trichoderma spp. are ubiquitous soil fungal species that are able to form endophytic (mutualistic) relationships with a number of plant species. Plant colonization by Trichoderma is thought to occur in three main stages: 1) physical penetration of the host plant 2) modulation of the innate plant immune response and 3) modulation of the R protein mediated immune response. Our current hypothesis is that during plant root interaction, Trichoderma modulates plant immunity in a similar manner to biotrophic plant pathogenic fungi, which utilize an array of proteins to counter the host plants immune response. However, very little is known about this beneficial interaction. To understand the plant-Trichoderma interaction a comprehensive understanding of the gene expression changes in both the fungus and the plant is required. We used RNA sequencing to determine the expression profiles at 3, 5 and 7 days of interaction between T. virens and Zea mays. Reads were mapped to publicly available genomes of T. virens Gv29.8 and Mo-17 maize using the junction mappers Bowtie2 and Tophat2. To identify proteins relevant to plant colonization Cufflinks and Cuffdiff were used to show differential expression levels at different time points. Transcripts highly up-regulated in Trichoderma during plant interaction were then identified and confirmed using qRT-PCR. A number of proteins similar to those involved in pathogenicity were identified, adding support to the theory that mutualists survive in plants in a manner similar to that of pathogens. A detailed analysis will be discussed in this presentation.

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Identifying targets for sustainable control of Sclerotinia diseases

Alicia Greenhill(1), Ian Porter(2), Ulla Benny(3), Jeffrey Rollins(3), Kim Plummer(1), Botany department, La Trobe University, Melbourne, Australia Department of Primary Industries, Victoria, Australia (3) University of Florida, Florida, USA (1) (2)

Sclerotinia diseases cause over A$100M loss to vegetable crops annually in Australia, with significant losses worldwide. Disease control is severely impeded by the pathogen’s ability to produce sclerotia; highly melanised structures crucial to the pathogen’s propagation, reproduction and survival. There are many genes known to be involved in sclerotial formation and maturation, however the exact pathway and contribution of different genes is not yet elucidated. This research used both a targeted and de novo approach to identify genes that may contribute to the formation and maturation of sclerotia in Sclerotinia. Melanin is vital to the robustness of sclerotia and may represent a target for sustainable control. Sclerotinia sclerotiorum produces melanin via the 1,8-Dihydroxynaphthalene (DHN) pathway. In vitro chemical inhibition and gene silencing were both used to reduce the amount of melanin produced by Sclerotinia. A silencing vector targeting a gene (tetrahydroxynapthalene reductase (4HNR), Ss1G_11315.3) on the DHN melanin biosynthetic pathway was stably transformed into S. sclerotiorum. Transformed isolates show variant phenotypes, and characterisation of these silenced isolates has been undertaken. In the second approach a number of Sclerotinia sclerotiorum mutants with sclerotia-minus or -aberrant phenotypes were characterised. These mutants were created via Agrobacterium-mediated transformation. In this process a short DNA sequence (T-DNA) is inserted randomly into the fungal genome. As the sequence of this T-DNA tag is known, the gene or region into which it has been inserted can be determined. T-DNA insertion points have been identified in a number of these mutants and the interrupted genes examined to determine their potential role in sclerotial formation.


SESSION 2D – BIOLOGICAL INTERACTIONS AND PLANT DISEASES

A study of Botrytis Virus X transmission and vegetative incompatibility in Botrytis cinerea

Mr Yanfei Zhou

Institute of Fundamental Sciences, Massey University [email protected]

Mr Gregor Kolbe

The University of Auckland [email protected] Gregor Kolbe , Matt Templeton , Mike Pearson (1)

Drought tolerance in endophyte-infected ryegrass - a transcriptomics study

(2)

(1)

School of Biological Sciences, University of Auckland, Private bag 92019, Auckland, New Zealand (2) The New Zealand Institute for Plant & Food Research Ltd, Private bag 92169, Auckland, New Zealand (1)

Botrytis cinerea, commonly known as grey mould is a necrotrophic ascomycete fungus which infects more than 200 crops and horticultural species worldwide. A conservative estimate from 2012 places global cost of B. cinerea control worldwide at ~1 billion euro per annum. Currently, control of B. cinerea relies heavily on the use of fungicides since there are few host crops where resistant cultivars are available. There are several concerns with the use of fungicides including the emergence of fungicide resistant strains and fungicide residue on the edible part of the crop which is often consumed without further processing. These factors are making biological control agents an attractive candidate to add to the B. cinerea control tool-box. Botrytis virus X (BVX) has some potential as a biocontrol agent for B. cinerea as it has been shown to reduce host pathogenicity under certain circumstances. However, the only known mode of horizontal transmission of mycoviruses is via hyphal anastomosis and B. cinerea has many genetically determined vegetative incompatibility (VI) groups, making it unlikely that two given isolates are able to successfully complete hyphal anastomosis. VI is a potential barrier to virus transmission, although it is suppressed in some fungi when anastomosis occurs during very early stages of germination, so called conidial anastomosis. In order to determine whether conidial anastomosis provided a mechanism for the transmission of BVX in B. cinerea a conidial anastomosis assay was optimized for imaging with fluorescence microscopy, in order to study anastomosis of incompatible strains expressing different nuclear localized fluorescent proteins. Six strains from four different compatibility groups and differing BVX status were all able to perform conidial anastomosis. An expression vector system optimized for B. cinerea with multiple antibiotic resistances and fluorescent protein markers was modified for nuclear localization by engineering a histone-GFP fusion protein using a bacterial in-vivo cloning system. The fluorescent markers enable differentiation between incompatible strains during the imaging of conidial anastomosis and recognition of the outcome of anastomosis between compatible and incompatible strains. The different antibiotic resistances also provide a means to re-isolate individual strains from a mixed sample which can be tested for BVX transmission using an established RT-PCR based method. Results of conidial anastomosis between incompatible strains will be discussed.

Yanfei Zhou(1) , Jan Schmid(1) , Richard D. Johnson(2) , David E. Hume(2) , Murray Cox(1) , Pierre-Yves Dupont(1) , Rosie E. Bradshaw(1) Bio-Protection Research Centre, Institute of Fundamental Sciences, College of Sciences, Massey University, Private Bag 11-222, Palmerston North 4442, New Zealand (2) AgResearch, Grasslands Research Centre, Private Bag 11008, Palmerston North 4442, New Zealand (1)

Infection of the pasture ryegrass Lolium perenne by the endophytic fungus Neotyphodium lolii enhances grass performance, but its benefit on grass drought tolerance is influenced by host genotype. However, little is known regarding how the endophyte improves grass drought tolerance and why this effect varies among grass genotypes. Knowing this would help us to make better use of endophytes, such as selecting and applying specific endophyte stains on grasses growing in arid areas; it would also increase our knowledge of this very important plant-microbe symbiosis. We selected a drought sensitive (DS) and a tolerant (DT) N. lolii infected ryegrass genotype from the same cultivar (Nine O One) in a glasshouse experiment. Endophyte-free grasses were generated from these and drought tolerance experiments involving genetically identical pairs of endophyte-infected (E+) and -free (E-) grasses were conducted in a controlled environment growth chamber, and both physiological and transcriptome analyses were done. Physiological parameters (including relative water content, osmotic potential, Fv/Fm and biomass) were determined and grass tissue (leaf, sheath, and root) was collected under two soil moisture conditions: 75% FC (field capacity) and 15% FC (maintained for one week to simulate drought conditions). The physiological results showed that endophyte enhanced drought tolerance in DT but not in DS plants. RNA was extracted from grass sheath and duplicate cDNA libraries for each grass in each condition were sequenced using Illumina next generation sequencing. More than 36 million 100 bp reads were obtained for each sample. Analysis of endophyte genes showed that 2,205 and 2,054 genes were differently expressed (> 2 fold) between endophyte in DT and DS grass respectively, under drought conditions. Analysis of grass genes showed an increase in numbers of endophyte induced differently expressed genes in both DSE+ and DTE+ grasses under drought conditions (3,359 and 1,626 respectively) compared to well watered conditions (2,862 and 799 respectively). Initial functional analysis indicates that endophyte genes, involved in alkaloid production, antioxidant activity and sugar metabolism, and grass genes involved in photosynthesis, lipid biosynthesis and sucrose-starch metabolism were differently expressed. Further detailed analysis is in progress.


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SESSION 2D – BIOLOGICAL INTERACTIONS AND PLANT DISEASES

Biological control of black rot of Brassica by a potential biocontrol agentPaenibacillus sp.

Dr Celeste Linde

Ms Hoda Ghazali-Biglar

Bio-Protection Research Centre [email protected] Hoda Ghazali-Biglar (1), John Hampton (1), Eline van Zijll de Jong (1), Andrew Holyoake (1), Alison Stewart (2) (1)

(2)

Bio-Protection Research Centre, Lincoln University, Lincoln 7647, New Zealand Marrone Bio Innovations Incorporation, California 95618, USA

Black rot is a widespread disease of brassicas caused by the seed-borne pathogen Xanthomonas campestris pv. campestris (Xcc). The aim of this research was to investigate the use of Paenibacillus for biological control of black rot on cabbage following application as a seed treatment, and to determine its effect on cabbage growth. Based on a dual culture assay, 24 isolates of Paenibacillus were categorized for their interactions with Xcc. Nine of these isolates with different bioactivity in suppression of Xcc in vitro were then screened for their capacity to reduce black rot symptoms on cabbage in pot trial assays. From these results one Paenibacillus isolate (P16), at concentration of 5×109 CFU/ml was selected as a potential biocontrol agent (BCA). To investigate if the disease control was provided via plant growth promotion, the BCA was co-applied with Xcc as a seed treatment. In the presence of Xcc, BCAtreated seedlings had significantly (P˂0.05) greater growth than the control. However, there was no significant difference in plant growth parameters between these treatments in the absence of the pathogen. To determine whether this BCA is rhizosphere competent and/or endophytic, cabbage seedlings grown from BCA-treated (1.5×107 CFU/seed) seeds were tested for the presence of BCA by real-time PCR using a specific primer pair based on the gyrB gene. Standard curves were generated for soil and plant samples, and the detection limit (1×103 CFU/g) determined. In rhizosphere soil, BCA density had decreased from 9.9×105 to 1.1×103 CFU/g by 11 days after sowing (DAS), and thereafter it was below the limit of detection. BCA population in the bulk soil was only detected up to 6 DAS, and was not recorded in plant samples, indicating either that the BCA is not endophytic or its density in the plant was below the detection limit. Overall, this BCA is rhizosphere competent only during early cabbage seedling growth, and is most probably not endophytic. However, it appears that the BCA, by reducing Xcc infection, better enables the seedlings to survive and grow.

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Evolution of Rhynchosporium commune on barley grass

The Australian National University [email protected] Celeste Linde Research School of Biology, Evolution, Ecology and Genetics, ,Bldg 44, Daley Rd, The Australian National University, Canberra, ACT 0200, Australia

Scald caused by Rhynchosporium commune is commonly found on barley as well as barley grass (Hordeum leporinum) in Australia, where barley grass is a common weed. Wild hosts of cereal diseases could play a significant role in the epidemiology and evolution of diseases. Disease evolution is significantly affected by population size and heterogeneity of the host. Although susceptible barley would harbour large population sizes of scald favouring increased pathogen evolution on barley, barley grass is genetically more diverse than cultivated barley and most likely harbour more resistance genes than barley. This heterogeneity could select for a pathogen population that is also genetically diverse with virulences that could render newly introduced resistance genes in barley ineffective. To investigate the effect of barley grass on the evolution of scald, pathogenicity of scald isolates from barley and barley grass was assessed on both hosts. Seed of barley grass in conspecific and heterospecific interactions was collected and increased to represent single mother lines. Twenty isolates each from barley and barley grass were inoculated onto 20 barley grass lines and 20 barley differentials. No significant difference in leaf area affected on barley was observed for isolates from barley and barley grass, thus isolates from barley grass are equally likely to affect barley than barley grass. In contrast, isolates from barley resulted in a significantly smaller percentage of leaf area infected on barley grass lines. This suggests that scald populations from barley rarely infects barley grass, however scald populations from barley grass has a high potential for gene flow to barley populations. Local adaptation of isolates from barley grass was noted as conspecific infections resulted in significantly higher levels of virulence than heterospecific infections. Barley grass therefor successfully acts as an ancillary host to scald harbouring highly virulent scald populations.


SESSION 2E – BIOLOGICAL INTERACTIONS AND PLANT DISEASES

Three diseases of potato plants caused by Spongospora subterranea: powdery scab on tubers, galls on roots, zoosporangia in root cells (root malfunction) Prof Richard Falloon

New Zealand Institute for Plant & Food Research Limited [email protected] Richard Falloon(1)(2), Ueli Merz(3), Ros Lister(1), Denis Curtin(1), Ruth Butler(1), New Zealand Institute for Plant & Food Research Limited, PB 4704, Christchurch 8140, New Zealand (2) Bio-Protection Research Centre, PO Box 85084, Lincoln University, Lincoln 7647, New Zealand (3) Plant Pathology, ETH Zürich, Universitästr. 2, CH-8092 Zürich, Switzerland (1)

The plasmodiophorid pathogen Spongospora subterranea f. sp. subterranea causes powdery scab of potato tubers, a longrecognised and economically important disease (“a disturbance that ..... interferes with ..... normal growth and development”). Powdery scab results from S. subterranea infection of host stolons (which develop into tubers). Each powdery scab lesion contains many sporosori, which are conglomerates of resting spores, and resting spores are the perennation life cycle stage of the pathogen. This tuber disease severely reduces the quality of potatoes for processing and fresh market sale, and causes down-grading or rejection of seed potatoes because infested seedlines are responsible for pathogen transmission to future crops. Spongospora subterranea also causes a second disease, galls (hyperplasia) on host roots. These are at first creamy-white, and later mature to dark brown as they become filled with sporosori. Galls on roots of potato and solanaceous weed hosts are responsible for inoculum build-up and longterm survival of the pathogen in soil. Field surveys have shown that Spongospora root galls occur commonly in potato crops, particularly where cool, moist (irrigated) soil conditions predominate. Zoospores of S. subterranea infect host roots to cause a third disease. Zoosporangia develop in root epidermis cells from zoospore infections, and release secondary zoospores to initiate subsequent cycles of root infection. Evidence is accumulating that zoosporangia in roots harm plant growth and productivity (shoot dry matter, tuber number and weight). Controlled experiments have demonstrated that inoculation with S. subterranea caused disrupted root function (water and nutrient uptake). Some potato cultivars that are highly resistant to powdery scab have been shown, nevertheless, to be very susceptible to zoosporangium infection and root hyperplasia. Spongospora subterranea is therefore responsible for three diseases of host plants; root malfunction (from zoosporangium infections), root hyperplasia and powdery scab on tubers. All three diseases have practical and economic importance for potato crop productivity (yield and quality).

Protecting commercial Australian potato genotypes from Verticillium wilt through identification of sources of resistance Ms Veradina Dharjono

The University of Melbourne [email protected] Veradina Dharjono (1), Paul Taylor (1), Tonya Wiechel (2), Nigel Crump (3) Department of Agriculture and Food System, Melbourne School of Land and Environment, The University of Melbourne, Victoria 3010, Australia Department of Environment and Primary Industries, Agribio Centre, Bundoora, Victoria 3083, Australia (3) ViC SPA, 1015 Myers Creek Road, Toolangi, Victoria 3777, Australia (1)

(2)

Verticillium dahliae is a major and persistent soil pathogen known to cause Verticillium wilt in potato (Solanum tuberosum L.). Host resistance remains as one of the most economical, environmental and efficient management practices for this disease. Prior to screening for resistance, a glasshouse bioassay was developed to optimise the inoculum density that would differentiate resistant genotypes in a glasshouse screening trial. Inoculum density was important in symptom expression as high inoculum level (106 spores/ml) was shown to kill potato plants. Tissue culture seedlings of Russet Burbank, a susceptible potato genotype, were established in sand in a glasshouse. After four weeks, the roots were dipped in water as a control and in six different inoculum concentrations 106, 105, 104, 5x103, 103, and 102 spores/ml for five minutes, followed by transferring plants to pasteurised potting mixed. Severity of foliar symptoms in growing plants was assessed and determined using a 0-5 visual qualitative scale. Results showed that an inoculum threshold level of around 103 spores/ml was required before the onset of wilt symptoms, although V. dahliae could be isolated from petiole and crown root tissue plants inoculated at 102 spores/ml. Seedlings of 13 commercial potato genotypes were subsequently inoculated with an inoculum level of 5x104 spores/ml using root dipped technique. Host reaction was determined at 10 weeks after inoculation based on visual symptoms and petiole or crown root tissue infection. Many genotypes exhibited typical symptoms of V. dahliae with infection of either petiole or crown root tissues, rendering them to be susceptible. Genotype Catani produced mild symptoms and was considered as moderately resistant. Two genotypes, Denali and Kennebec only produced slight symptoms and hence were considered as resistant. These potential resistant genotypes are undergoing further glasshouse trials and may be used as part of an integrated disease management practice to control Verticillium wilt.


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SESSION 2E – BIOLOGICAL INTERACTIONS AND PLANT DISEASES

Insects as vectors of Quambalaria pitereka, the significant shoot, flower and bud blight pathogen of Corymbia calophylla in southwest Western Australia

Dr Carla Eaton

Massey University [email protected]

Briony Williams

Murdoch University [email protected] Briony Williams(1), Trudy Paap(1), Cielito Marbus(1), Giles Hardy(1), Treena Burgess(1) (1)

State Centre of Excellence for Climate Change, Woodland and Forest Heath, School of Veterinary and Life Sciences, Murdoch University, Murdoch, 6150, Western Australia

Marri (Corymbia calophylla) is a keystone species in forests of the south-west of Western Australia, providing fauna such as the critically endangered Carnaby’s Cockatoo (Calyptorhynchus latirostris) with food and shelter, and pollen and nectar for honey bees. The primary pathogen Quambalaria pitereka was introduced to Western Australia from the eastern states in the early 1990s and has since spread across most of the C. calophylla range. This pathogen causes leaf, flower and shoot blight in Marri, and as its incidence and severity increases, it is likely to deeply impact the ecosystem services that Marri provides. Little is known about how the pathogen is disseminated. The present study has shown that a range of insect species are associated with infected foliage, flowers and fruit and are likely to act as vectors of the pathogen. Quambalaria cyanescens, a non-pathogenic species which grows in close association with Q. pitereka, was isolated onto selective agar from bees, ants, weevils and flies collected from Marri showing symptoms of the blight. Insects have not previously been shown to be vectors of Quambalaria species. Since Q. cyanescens outgrows Q. pitereka on isolation media, molecular analysis was conducted to confirm the presence of Q. pitereka on these insects. To do this, specific primers were developed for Q. pitereka, Q. cyanescens and other Quambalaria species. Insects shown to carry Q. pitereka and Q. cyanescens spores are now being used in pathogenicity experiments to determine their ability as vectors in the disease syndrome. This study may open up avenues for the management and control of the disease. Further studies will look at potential biocontrol agents that could potentially be disseminated by the insect vectors, such as the honeybee.

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Friends don’t eat friends: loss of endophyte mutualism triggers activation of host degradation

Carla Eaton(1), Pierre-Yves Dupont(1), Murray Cox(1), Aiko Tanaka(2), Barry Scott(1) (1)

(2)

Institute of Fundamental Sciences and The Bio-Protection Research Centre, Massey University, Palmerston North, New Zealand Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan

Associations between the fungal endophyte Epichloe festucae and perennial ryegrass require signalling between the fungus and its host in order to regulate fungal growth in planta and maintain these beneficial associations. In recent years, a number of fungal pathways essential for this signalling have been identified, including the NADPH oxidase/reactive oxygen species signalling pathway, stress-activated MAP kinase pathway, and cell integrity pathway. Disruption of these pathways leads to a dramatic switch from mutualistic to pathogenic-like association with perennial ryegrass. Infected plants display severe stunting and prematurely senesce only weeks after inoculation, in comparison to the generally asymptomatic wild-type associations. To identify the molecular mechanisms underlying this symbiotic switch we pioneered the novel approach of using high through-put mRNA sequencing to identify plant and fungal gene expression differences between the mutualistic wild-type symbiotum and pathogenic-like ΔsakA stress-activated MAP kinase mutant symbiotum. This resulted in identification of a putative symbiotic gene set of 1202 genes. In this study, we take this approach further in order to narrow this symbiotic gene set. To this end, we performed mRNA sequencing of two additional symbiotic mutants, the main catalytic component of the NADPH oxidase, noxA, and C6 zinc finger transcription factor, proA. Comparison of the genes differentially expressed among these three symbiotic mutants identified a core symbiotic gene set of 181 genes. The majority of these genes (79%) were up-regulated in the symbiotic mutants relative to wild-type, suggesting they may play a role in promoting the switch towards pathogenism. In support of this, a number of putative transporters and plant cell wall-degrading enzymes were identified. Interestingly, around 10% of the core gene set had no homologues in the NCBI non-redundant protein database, implying that these may be unique to the Clavicipitaceae. Interrogation of 11 additional Clavicipitaceae genome sequences revealed that 13 of these genes are unique to the Epichloe endophytes. Of these, seven were predicted to encode secreted proteins smaller than 200 amino acids. These are two hallmarks of fungal effector proteins, raising the possibility that Epichloe endophytes produce effectors to evade host defenses and establish systemic colonization.


SESSION 3A – BIOSECURITY

Identification of trapped insects and associated microbes by next generation sequencing Simon Bulman

Plant & Food Research [email protected]

Increasing the Genetic Diversity of Sugarcane Germplasm through Continuous Introduction of Disease-Free Foreign Varieties Dr Fe Dela Cueva

Simon Bulman, Sam Beard, Ian Scott, Grant Smith

University of the Philippines Los Banos [email protected]

The New Zealand Institute for Plant & Food Research Limited, Gerald Street, Lincoln 7068, New Zealand

Fe M. Dela Cueva(1), David B. Cristobal(1) , Chona R. Untal(2), Rosalyn T. Luzaran (2), Merle B. Palacpac (3) Institute of Plant Breeding, CSC, CA, UPLB, Laguna Philippine Sugar Research Institute Foundation, Inc.,Victorias City, Negros Occidental (3) Plant Quarantine Sevice,Bureau of Plant Industry, San Andres, Manila (1)

Increased global movement of people and produce is accompanied by heightened threats from insect pests. The arrival of new pests and associated pathogens can have severe consequences for agriculture, as demonstrated by the incursion of the tomato potato psyllid into New Zealand. Simple, reliable detection systems could provide early discovery or delineation of outbreaks, allowing eradication or enhanced management. However, there are few systems for routine untargeted surveillance of insect incursions anywhere in the world; monitoring and identifying insects is expensive. We have set out to use next generation sequencing to rapidly and simply identify mixed insects and the microbes that they carry. Known combinations of sap-sucking insects (psyllids, aphids, whiteflies, thrips) were assembled and DNA extracted. Amplicons were generated from these mixtures with a range of conserved PCR primers for the cytochrome oxidase I gene. The amplicons were subject to barcoded 454 FLX pyrosequencing. Although all primer pairs were shown to be effective against individual DNAs, comparable detection of insects within mixtures was not obtained and high levels of bias were instead evident. Aphids were detected by all primer combinations with the mtd6/ HCO2198 primers almost exclusively favouring detection of aphids. C1-J1709/HCO2198 favoured the psyllid Bactericera cockerelli largely to the exclusion of aphids and the thrips Frankliniella occidentalis. This result suggested that insect biomass was not the key determinant of detection. In general, we saw surprisingly little improvement after introducing degeneracy into the conserved primers to make them match a broader selection of the insects. Modification of mtd6 led to better detection of thrips and psyllids, but it remained poor for whitefly. Inclusion of the HCO2198 primer appeared important to broaden detection of insect genera. In addition to the simple insect mixtures, larger combinations of 20 insects captured in yellow bowl traps (in propylene glycol) in the field were also examined. DNA sequences from these mixtures were again dominated by sequences from only a few of the insects. Overall, it appears that detecting a wide range of insects with such PCR-based techniques will require the use of more than one primer combination. Ribosomal 16S bacterial amplicons have recently been generated from the DNA mixtures. Pyrosequence data from these amplicons is being processed with the aim of detecting and identifying bacteria carried by the insects.

(2)

Introduction of foreign sugarcane varieties is an indispensable step in the continuous development for new sugarcane breeds. These introduced varieties provide a wide array of ingredients for breeders to craft superior canes. Sugarcane varietal exchange among Southeast Asian countries was strengthened in 2001 when Common Fund for Commodities (CFC) funded a project with Philsurin and UPLB. The genetic base of the Philippine sugarcane germplasm collection was widened through the project. Realizing the importance of varietal exchange, efforts was made to expand this endeavour to other sugarcane producing countries even after the project ended in 2006. To prevent incursion of new strains of pathogens or pathogens that are unrecorded in the country, strict postentry quarantine actions through routine disease detection and monitoring was implemented through collaborative efforts of PHILSURIN, IPB, and BPI. To date, more than 300 elite varieties had been introduced to the Philippines. These varieties came from Thailand, Indonesia, Malaysia, Bangladesh, Japan, China, Australia, France, USA, Vietnam, Pakistan and Mauritius. All the materials had undergone the routine disease indexing scheme at the post-entry quarantine glasshouse for two years, and another year under the open field quarantine. Both antibody- and nucleic acid-based disease detection techniques are being employed to ensure the release of disease-free varieties either commercially or for breeding purposes. At present, three varieties are being used by sugarcane planters, three varieties are being tested in 11 locations across the country. Some varieties are being used in local hybridization. Key words: sugarcane, varieties, diseases, quarantine, disease detection


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SESSION 3B – BIOSECURITY

Defining core pan-genomes of species in ‘Candidatus’ Liberibacter for the development of new diagnostic tools

Fusarium vascular infection of oil palm: Epidemiology, genetic diversity and molecular diagnostic tools

Dr Grant Smith

Dr Mohd Hefni Rusli

Sarah Thompson (1)(2), Chris Johnson (3) , Ashley Lu(1)(2) , Rachel Mann(2) (4) , Rebekah Frampton(1), Mark Fiers(1) , Andrew Pitman(1)(2) , Ian Scott(1) , Neil Gudmestad(3) , Brendan Rodoni(2)(4), Grant Smith(1)(2)

Mohd Hefni Rusli(1), Richard Cooper (2), Alan Wheals (2), Idris Abu Seman

The New Zealand Institute for Plant & Food Research Limited [email protected]

The New Zealand Institute for Plant & Food Research Limited, Gerald Street, Lincoln 7068, New Zealand (2) Plant Biosecurity Cooperative Research Centre, Canberra, ACT 2617, Australia (3) Department of Plant Pathology, North Dakota State University, Fargo 58108, USA (4) Biosciences Research Division, Department of Primary Industries, AgriBio, La Trobe University, Bundoora, Victoria, 3083, Australia.

Malaysian Palm Oil Board [email protected] (1) (1)

(1)

The ‘Candidatus’ Liberibacter genus contains five unculturable α-proteobacterium species (asiaticus, americanus, africanus, solanacearum and europeaus). A sixth species Liberibacter crescens is culturable, and is thus not categorised as ‘Candidatus’. The first three species are implicated as the causal agents of Huanglongbing (HLB) of citrus, which is generally regarded as the most serious and destructive disease of citrus in the world. Ca. L. solanacearum is considered to be the casual agent of Zebra Chip disease of potato (and causes pathology on a range of other solanaceous plants). The remaining two species are considered to be endophytes of pear/ scotch broom and papaya respectively. All five Ca. Liberibacter species are associated with, and vectored by, a range of species of phloem-feeding psyllids (Hemiptera:Psyllidae or Hemiptera:Triozidae). L. crescens has no known insect vector. Four haplotypes of Ca. Liberibacter solanacearum (CLsol) have been described based on SNPs in the rRNA, intergenic spacer or ribosomal protein regions. The genome of CLsol haplotype B has been published revealing a genome of approximately 1.25 Mbp. Draft genome assemblies of haplotype A from one USA source and two independent New Zealand sources have revealed significant changes between the haplotype A and B genomes.. The three CLsol haplotype A draft genomes have significant colinerality with the exception of the prophage domains. In these regions, the two NZ domains are similar to each other, and different from the USA prophage region sequence. The three haplotype A genomes also have a greater number of SNPs relative to the haplotype B genome. The origin of CLsol in New Zealand is believed to be via incursions of the tomato potato psyllid (Bactericera cockerelli) from the USA. The genetic similarity of the current assemblies of the two NZ CLsol genomes (from diverse solanaceous sources) may suggest a limited incursion of the genetic diversity of this bacterium into NZ. As more Liberibacter genome data are gathered this preliminary hypothesis can be robustly challenged. Further CLsol genomes are being sequenced to contribute to a pan-genome for this species. To define a wider Ca. Liberibacter pan-genome, and provide a context for a CLsol pan-genome, sources of Ca. L. asiaticus and other species from a wide range of plant/ insect hosts and geographic regions are currently being sequenced. Together this data will facilitate the development of robust molecular-based diagnostic tools for the detection of Liberibacter species and its haplotypes.

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(2)

Malaysian Palm Oil Board (MPOB). No. 6, Persiaran Institusi, Bandar Baru Bangi, 43000 Kajang Selangor, Malaysia Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, UK

Vascular wilt disease caused by Fusarium oxysporum f. sp. elaeidis (Foe) causes a devastating disease of oil palm in West and Central Africa. However, this disease has not been reported in South East Asia, in spite of long term importation for breeding purposes of African seed and pollen, known to be often contaminated with Foe. Malaysia is the second largest palm oil producer in the world and Foe remains a major threat to this industry, especially as this study shows four current palm genotypes grown there are susceptible. This research was conducted in order to help Malaysia avoid and/or be prepared for this potential problem. Disease epidemiology was studied in plantations in Ghana. Statistical analysis showed the disease mainly occurred in clusters, implying root-root transmission rather than aerial spread by spores. Many Foe isolates were obtained for genetic analysis from diseased palms, including 10 per cent from 21 symptomless trees. This shows that visual disease surveys are flawed. The only practical, sustainable approach to controlling Fusarium is by breeding disease resistant palm lines. The success of this strategy depends on the variability of Foe isolates. Resistance should be stable because this analysis showed Foe isolates have a monophyletic origin. Molecular diagnostic tools were developed for (1) rapid detection and quantification of Foe in seed and pollen for quarantine purposes in order to prevent transcontinental spread of Foe, (2) to test efficacy of putative disease resistant or tolerant palm genotypes, and (3) to facilitate epidemiological studies involving palm tissues and soils. Primers were designed for detecting the species F. oxysporum, based on the translation elongation factor gene (TEF-1α), superior to the existing ones used currently at quarantine. The first Foe-specific primers to be developed were based on a virulence effector gene that excluded 70 other phylogenetically closely related Fusarium species from various hosts and origins.



Development of real-time PCR assays for the detection of the myrtle rust fungus Puccinia psidii Dr Jeyaseelan Baskarathevan Ministry for Primary Industries [email protected]

Jeyaseelan Baskarathevan, Robert Taylor, Wellcome Ho , Brett Alexander Plant Health and Environment Laboratory, Ministry for Primary Industries, PO Box 2095, Auckland1140, New Zealand

Myrtle rust (Puccinia psidii) is expected to arrive into New Zealand in the near future. Early detection of P. psidii would be important to determine biosecurity options to prevent further spread as this pathogen can be spread quickly by airborne spores. Thus it is important to have a fast and accurate method to detect the P. psidii at the early stages of infection. Currently, only a conventional species-specific nested PCR assay is available for the detection of P. psidii. In this study, multiple sets of primers and TaqMan probes were designed using conserved sequences of the internal transcribed spacer (ITS) region and the beta-tubulin (βt) gene of P. psidii. A total of seven TaqMan real-time PCR assays, including three targeting the ITS region and four targeting the βt gene, were developed for the detection of P. psidii. These TaqMan assays were able to detect the genomic DNA of all 13 P. psidii isolates obtained from Brazil, Hawaii, and Australia. High specificity of these assays were confirmed by testing these assays against seven other closely related Puccinia species and DNA extracted from 13 healthy myrataceous plant species commonly found in New Zealand. The sensitivity of all three ITS real-time PCR assays were at least 100 times more sensitive than the βt real-time PCR assays. Among the three ITS real-time PCR assays, the assay with the highest sensitivity was able to detect P. psidii DNA down to 100 fg, which is approximately the amount of DNA from a single spore. This ITS real-time PCR assay was selected for further validation and was shown to be able to detect P. psidii from symptomatic as well as non-symptomatic leaf samples collected from an infected host in Australia. The newly developed ITS real-time assay takes around one and a half hours to run and has proven to be four times faster than the conventional nested PCR assay.

Eradication of Chestnut blight in Victoria Australia Martin Mebalds

Department of Environment and Primary Industries Victoria [email protected] Martin Mebalds(1), Patrick Sharkey(1), William Washington W(1), Brendan Ralph(2) Department of Environment and Primary Industries Victoria, Biosecurity Victoria, Knoxfield Centre, Private Bag 15, Ferntree Gully DC, VIC 3156, Australia Biosecurity Victoria (2) Department of Environment and Primary Industries Victoria, Biosecurity Victoria, Great Alpine Road ,Ovens, VIC 3737 (1)

Chestnut blight (Cryphonectria parasitica) was first detected in Eurobin, north east Victoria in September 2010. A survey of 322 commercial groves and 158,000 chestnut and oak trees defined the extent of the incursion to 9 groves in the Ovens Valley. All host trees within 100m of an infected tree were removed and burnt. A four year surveillance program was initiated to detect any properties with newly emerging infections and to collect evidence for a declaration of eradication. A further two infected groves were subsequently detected in 2011 and 2012. All trees on the grove detected in 2011 were removed and destroyed. The last detection of chestnut blight in 2012 manifested as one small lesion on one tree on one property. The tree was immediately removed and destroyed. Fortnightly monitoring of the infected grove for the next three months did not detect any further infections, however, all trees within 10 m of the infected tree were destroyed. Samples of 1,672 nuts from 25 trees at 10, 25, 50 and 100m from the infected tree tested negative for the presence of C. parasitica. A total of 5,329 chestnut and 38 oak trees were destroyed in the eradication phase of the response to June 2013. Owners of commercial chestnut groves received owner reimbursement costs under the Emergency Plant Pest Response Deed, a cost sharing arrangement between federal and state governments and industry. With the exception of the last infected grove, all other groves have been surveyed at least 15 times, without a reappearance of the disease. It is expected that given no further detections, Victoria will be able to declare eradication of chestnut blight in the Ovens Valley by spring 2013 and eradication on the last grove by mid 2014, two years after the last detection.


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Diversity and classification of Phellinus noxius in Queensland and New South Wales

Checklists, Quarantine and Trade continuing challenges for developing countries

Ms Louise Shuey

Prof Lester Burgess

Louise Shuey (1), Alistair McTaggart (2), Geoff Pegg (1), Elizabeth Dann (2)

Lester Burgess(1)

Queensland Department of Agriculture, Fisheries and Forestry, The EcoSciences Precinct, GPO Box 267, Brisbane Qld 4001, Australia (2) Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, The EcoSciences Precinct, GPO Box 267, Brisbane Qld 4001, Australia

(1)

Queensland Department of Agriculture, Fisheries and Forestry [email protected]

(1)

Phellinus noxius (Hymenochaetaceae, Agaricomycetes) is a wood rotting fungus distributed in tropical regions including Southeast Asia, Central America, Africa and Australia. In natural settings it is saprobic, but in disturbed areas or monoculture it is often pathogenic, and causes tree deaths. It causes brown root rot of a wide range of hosts from angiosperms to gymnosperms. Phellinus noxius impacts productivity of avocado (Persea americana) and hoop pine (Araucaria cunninghamii) in Queensland and northern New South Wales. We studied the diversity of 90 isolates from several hosts and geographical locations around Queensland and northern New South Wales in order to determine 1) whether one pathogen was responsible for disease on such a wide host range, and 2) potential that basidiospores are involved in spread of the disease. Initial fingerprinting studies showed the population was variable and possibly more than one species existed. A phylogenetic analysis of the ITS and IGS regions recovered no clear genealogical groups that shared a common host or location. This may indicate P. noxius is a species complex. We conducted a separate study to determine the systematic position of P. noxius. Comparison of the LSU and ITS regions to other taxa of the Hymenochaetaceae showed P. noxius was sister to Phellinus s. str. , and may not be a true Phellinus .

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University of Sydney [email protected]

Faculty of Agriculture and Environment, The University of Sydney, Sydney, 2006

Developing countries continue to face major challenges in respect of trade issues relating to quarantine matters. This is particularly so for countries in the early stages of development. In my Presidential Address on ‘Biosecurity, Trade and Plant Pathology’ in 2003 I argued the case for greater involvement by experienced plant pathologists in developing countries. The recognition of this need by governments and international aid agencies has led to increased support for training activities and facilities. It is commendable that many plant pathologists in APPS are involved. However the development of accurate checklists of plant pathogens for a developing country or local area remains a daunting task as is the maintenance of culture collections and herbaria of disease specimens. In this abstract I briefly discuss two of the major challenges, and propose how we might help improve capacity building activities. I will focus on fungal and fungal-like pathogens for this purpose. A key challenge especially for countries in an early stage of development is that staff designated as plant pathologists may have little or no formal training in plant pathology, and often limited University training. Limited English may also be a handicap. Attendance by such staff at short regional workshops in English is usually of little benefit. My experience is that initial training in laboratory procedures, diagnostics, pathogenicity testing and survey methods is usually best done through handson programs in-country over a minimum of four to five weeks accompanied by basic English tutoring as discussed elsewhere. Furthermore a volunteer plant pathologist who can consolidate the initial training and lay the groundwork for further training activities in laboratory and field is a great asset. Another major challenge is accurate identification to species level and support from an internationally recognised herbarium for deposition of cultures and/or diseased specimens. We need to expand such support from taxonomists and culture collections. We also need to help trainees develop and maintain accurate records through an electronic and hard copy database. The recent welcome changes to import conditions in Australia for nucleic acids (excluding viroid RNA) for example will facilitate identification of fungal and fungal-like pathogens on behalf of developing countries, especially as basic facilities are developed in-country to enable extractions locally. I believe that APPS can do more to help promote such programs and liaise with funding agencies. APDN already provides an excellent avenue for disease notes.



A new era for government and industry partnerships on biosecurity in New Zealand Lois Ransom

GIA Secretariat [email protected] Lois Ransom 25 The Terrace, Wellington, New Zealand

Biosecurity is a shared responsibility and benefits all New Zealanders. With 72% of exports derived from primary production, the effective management of biosecurity risks is essential to New Zealand’s economy. New Zealand’s natural environment and its unique native flora and fauna draw tourists from all over the world and are also vulnerable to biosecurity risks. A recently completed Government Industry Agreement (GIA) for Biosecurity Readiness and Response has laid the foundation for better biosecurity outcomes for New Zealand through partnership arrangements built on joint decision-making and cost sharing. A GIA Deed outlines the principles for the partnership between the New Zealand Ministry for Primary Industries (MPI) and primary industries that sign the Deed, and is enabled by the Biosecurity Act 1993. The Deed also sets out the commitments that each Signatory makes to engage in the wider biosecurity system and co-invest to improve collective capacity and capability of industry and government to prepare for and respond to exotic pests and diseases. It provides for the development of Operational Agreements, which are a binding contract between MPI and industry parties to each Agreement, to co-invest in and deliver actions that achieve specific biosecurity readiness and response outcomes. These outcomes may relate to specific unwanted organisms or groups of organisms, or target improvements to overall biosecurity readiness and/or response. The Deed describes minimum commitments for MPI, industry and the partnership. These capture expectations that the Signatories will maintain or improve diagnostic capacity and capability, technical and operational expertise for risk analysis and pest management, enhanced detection, analysis and management of emerging biosecurity risks, stakeholder awareness and communication, as well as capability and investment in surveillance to detect and report new organisms. Biannual biosecurity fora will be held to discuss the biosecurity system. An independent GIA Secretariat was established in 2012 and will assist a Deed Governance Group, made up of Deed Signatories, to implement the Deed. The Deed is available to all primary industries including plant, animal and aquatic sectors.

Stripe smuts of grasses: one lineage or high levels of polyphyly Mr Kyrylo Savchenko University of Haifa [email protected]

Kyrylo G Savchenko(1)(2), Lori M Carris(3), Lisa A Castlebury(4), Solomon P Wasser(1)(2), Vasyl P Heluta(2), Eviatar Nevo(1) Department of Evolutionary & Environmental Biology, University of Haifa, Mt Carmel, Haifa 31905, Israel (2) M.G. Kholodny Institute of Botany of the NAS of Ukraine, 2 Tereshchenkivska St., Kyiv 01601, Ukraine (3) Department of Plant Pathology, Washington State University, Pullman, WA 99164, USA (4) USDA-ARS, Systematic Mycology & Microbiology Laboratory, 10300 Baltimore Avenue, Beltsville, MD 20705, USA (1)

Stripe smut of grasses Ustilago striiformis s.l. is caused by a complex of smut fungi widely distributed over temperate and subtropical regions. The disease results in the shredding and death of leaf tissue following the rupture of long sori in the leaves. Nearly 100 different grass species in more than 30 genera are parasitized and during the last two centuries more than 30 smut taxa have been described for members of this complex. In spite of wide application of various fungicides, the economic losses induced by these diseases worldwide are still dramatic for lawn and forage grass industries. The present study is a first attempt to clarify the taxonomy and phylogeny of the stripe smuts of grasses by analyzing both morphological and molecular data. More than 200 specimens from different continents and from all genera of the known host plants were examined and analyzed. DNA extracted from teliospores from 31 specimens from different hosts from Europe, Asia, and North America was used to amplify ITS and LSU regions used in phylogenetic analyses. The results of Maximum Parsimony and Bayesian analyses demonstrated that there are several lineages of stripe smut fungi. Hierarchical clustering analyses of morphological characters assessed with light and scanning electron microscopy (spore size and ornamentation) showed high support for the differentiation of two clades as distinct from U. striiformis s.l., i.e., Ustilago nunavutii sp.nov. and U. bromina. Two additional clades, Ustilago striiformis s.s.on Holcus and a clade containing specimens from Elymus, were identified with molecular data although morphological differences were not apparent. Further studies will likely reveal more lineages of these complex and polyphyletic fungi.


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SESSION 3C – BIOSECURITY

Keeping one step ahead of invasive species: Using an integrated framework to screen and target species, for detailed biosecurity risk assessment.

Dr Bevan Weir

Landcare Research [email protected]

Mr Sunil Singh

Bevan S Weir, Peter R Johnston

CSIRO Ecosystem Sciences [email protected]

Landcare Research, Private Bag 92170, Auckland 1142, New Zealand

Sunil Singh (1)(2)(3), Mike Hodda (1), Gavin Ash (1)(2) CSIRO Ecosystem Sciences, Canberra, ACT, 2601, Australia Graham Centre for Agricultural Innovation (an alliance between Charles Sturt University and the NSW Department of Primary Industries)Wagga Wagga NSW, 2678, Australia (3) Cooperative Research Centre for National Plant Biosecurity, Bruce, ACT, 2617, Australia (1) (2)

Predicting which species will become invasive in any country or region before they arrive is necessary to devise and implement counter-measures to minimise the costs of biological invasions. This is literally keeping one step ahead of invasive species. A structured and systematic approach for screening large numbers of species and identifying those likely to become invasive is proposed in this paper. The Pest Screening and Targeting (PeST) framework integrates heterogeneous information and data on species biogeography, biotic and abiotic factors to first determine an overall threat index, then uses this index to identify species for a second, more detailed, threat evaluation process to provide a final ranking. Using the PeST framework, 97 species of Plant Parasitic Nematodes (PPN) were evaluated for their biosecurity threat to Australia. The species identified as greatest threats included both new and currently-recognised species. The former included Heterodera zeae, Meloidogyne graminicola, M. enterolobii, M. chitwoodi and Scutellonema bradys, while the latter included Bursaphelcnhus xylophilus, Dityelenchus destructor, Globodera pallida, Heterodera glycines and H. filipjevi. Of the ten criteria used in the PeST framework, emerging pest status, pathogenicity, host range and the SOM index (based on species biogeography) were often the most critical in assessing threat. The PeST framework also identified species where research to fill in critical knowledge gaps will be most beneficial. Where data was available, the information and associated metadata gathered for the PeST framework can be used to produce species profiles useful for management of the high-threat pests identified.

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Recent changes in Colletotrichum taxonomy

Colletotrichum fungi are considered to be one of the top ten important plant pathogens in the world, and have had a history of confusing taxonomy. The last major revision of the genus was done by von Arx in 1957 where many different species described on the basis of host association were synonymised to just a few names based on morphological characters. Over the past five years a major taxonomic initiative was undertaken by several research groups worldwide to clarify the taxonomy of this important pathogen. Multigene sequencing and morphological characters of voucher specimens were used to modernise the taxonomy and species concepts of the genus. This work revealed the presence of “species complexes” such as Colletotrichum gloeosporioides sensu lato that currently comprises 25 species, some of which are well established pathogens such as C. musae on bananas, while others are newly described such as the predominately endophytic C. aotearoa. Another challenge is to comply with a recent change to the ICN nomenclatural code removing dual nomenclature for fungi, this means that the Glomerella teleomorph names need to be linked and synonymised with Colletotrichum names where possible, or given new Colletotrichum names. There is the persistent problem of old names that do not have a specimen and no modern concept of what the species is. Most of these names are obscure but some such as C. crassipes are still in common use. These major changes are of particular importance for biosecurity and trade, but also for plant pathology research, some reports of variable pathogenicity of a Colletotrichum species may in fact be due to the presence of multiple cryptic species.A Colletotrichum identification website has been set up at “Q-Bank” that uses multigene data and the option of morphological characters to help quickly identify Colletotrichum species.


SESSION 3C – BIOSECURITY

Dutch elm disease in New Zealand: From eradication to management

Mango malformation in the Northern Territory of Australia

Dr Beccy Ganley

Lucy Tran-Nguyen

Beccy Ganley, Lindsay Bulman

Jose R Liberato,, Lucy TT Tran-Nguyen,, Andrew M Daly,, Stephen West

Scion (New Zealand Forest Research Institute Ltd.), 49 Sala Street, Rotorua 3046, New Zealand

Department of Primary Industry and Fisheries, GPO Box 3000, Darwin, NT 0801, Australia

Ophiostoma novo-ulmi, the causal agent of Dutch elm disease (DED) is considered to be one of the 20 worst pests to have been introduced into New Zealand. The pathogen was first discovered in New Zealand in December 1989 in an inner Auckland city park. Immediately after O. novo-ulmi was discovered an eradication campaign was begun by the Ministry for Primary Industries along with surveillance programmes for Scolytus multistriatus, the only known vector of the pathogen in New Zealand. Initially the eradication campaign looked promising as there was a steady decline in the number of infected trees and locations. However, an evaluation of the program concluded that the disease was actually only being effectively managed and contained, and funding of the DED programme was discontinued with responsibility handed over to local authorities. Although limited surveys and sanitation felling are still being completed, there has been a rise in the detection and spread of both O. novo-ulmi and S. multistriatus in New Zealand. We review the eradication campaign and lessons learnt for future eradications, the current status and spread of O. novo-ulmi and S. multistriatus in New Zealand, and the control or management options for DED. This includes the feasibility of a regional-based eradication of DED and the use of viral biological control against O. novo-ulmi.

Mango malformation (MMD) is an important disease of mango (Mangifera indica) in many production areas around the world. It is caused by Fusarium mangiferae, F. sterilihyphosum, F. mexicanum and F. tupiense. MMD symptoms have been associated with several other Fusarium species. In November 2007, MMD was detected at DPIF’s research station in the Northern Territory (NT). F. mangiferae was identified and subsequently gazetted as declared and notifiable pathogen. The emergency plant pest response included back/forward tracing which identified that prior to the detection of MMD at the research station, plant material, from the exact same source had been distributed across the entire Australian mango breeding programs to both Government and private breeders, and then propagated and distributed nationally to the Australian Industry as planting material. Since 2007, F. mangiferae has been detected in nine mango trees and a new species of Fusarium was associated with MMD-like symptoms in 24 mango trees and three seedlings. Attempts to prove the pathogenicity of this new species have been unsuccessful. Several other Fusarium species have been associated with 21 mango trees with atypical symptoms of deformed inflorescences and distorted shoots. From these, F. proliferatum was found to be associated with 14 trees. The identification of the Fusarium species from MMD and associated MMDlike plant symptoms was based upon multigene analyses of single-spore derived cultures. Since October 2008, no MMD suspect samples have been received from mango growers and all detections resulted from DPIF’s MMD surveys. Up to 2012, all F. mangiferae infected trees were eradicated. Mango trees associated with the new species of Fusarium and F. proliferatum were eradicated from two DPIF’s research stations but not from private properties as these Fusarium species were not recognised as emergency plant pests. In 2012, an MMD survey was carried out during flowering and F. mangiferae was detected on six trees with atypical MMD symptoms. It is likely that these atypical symptoms could easily be overlooked in a survey and there are doubts about the efficacy of visual detection of infected inflorescences and shoots. To add to this difficulty, a high incidence of deformed or compact inflorescences was observed in two surveyed orchards where plant growth regulators were applied. These flowers senesced and fructified as normal and most attempts to isolate Fusarium from them were unsuccessful. At present MMD and MMD-like symptoms do not seem to be an economic problem in the NT.

Scion [email protected]

Department of Primary Industry and Fisheries [email protected]


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SESSION 4A – DISEASE MANAGEMENT

Big achievement from a handful of high performing varieties: a concept in the context of crop health for wheat in Western Australia

Control of crown canker of passion fruit (Passiflora edulis Sims.) – an acute disease problem for New Zealand passion fruit growers

Dr Moin Salam

Dr Pia Rheinländer

Moin U. Salam,, Kawsar P Salam,, Geoff J. Thomas,, Ciara Beard,, William J. MacLeod,, Arthur J. Diggle, and, David G. Bowran

Pia Rheinländer(1), Michael Spiers (2), Mark Andersen(1), Robert Fullerton(1)

Department of Agriculture and Food Western Australia [email protected]

Department of Agriculture and Food Western Australia, 3 Baron-Hay Court, South Perth, WA 6151, Australia

Australia and New Zealand can potentially become the food bowl of Asia by 2050. According to ANZ insight report ‘Greener Pastures: The Global Soft Commodity Opportunity for Australia and New Zealand’ (ANZ 2012), this can be achieved by meeting seven challenges, one of which is improved focus of research and development (ANZ 2012). Export of Western Australian (WA) wheat, currently worth A$1881 million per annum, can play a significant role in this endeavour. This study aimed to develop a practical crop health system to increase wheat production in WA. To achieve this aim, we identified the main driver of wheat production, and developed a system that respects the primacy of this driver and addresses management of the major foliar diseases of wheat within that constraint. Results, as supported by correlation and mean squared variation analysis, show that ‘area’ of wheat planted was the driver of wheat production from the 1950s through the 1970s; whereas, ‘yield’ has become the driver, replacing ‘area’ from the 1980s onward. The ‘yield’ is driven by ‘constraints free yield potential’ of varieties. During the last 20 years, growers have been using, on average, 45 varieties each season; however, the top variety each season occupied about 25% and the top 8 varieties about 80% of total area. These results clearly show, as the Pareto principle of ‘the law of the vital few’ describes, that targeting a handful high impact varieties can be instrumental in achieving big gains in WA’s wheat production. We have developed a conceptual wheat health system that retains the growers’ variety adoption practice, and address crop health factors. Most of the yield loss from wheat diseases in WA results from septoria nodorum blotch (Stagonospora nodorum, teleomorph: (Phaeosphaeria nodorum) (SNB) and yellow leaf spot (Pyrenophora tritici-repentis) (YLS) (Murray & Brennan, 2008). We applied the wheat health system to address these two diseases. Based on growers’ current variety choices and a meta-analysis using 1980-2011 field trial data we have calculated the yield response, stratified according to the disease resistance level of the varieties, of one application of fungicide to control these two diseases. Given the response likely to be achieved in high and medium rainfall regions of WA, a 252,823 tonne increase in production, valued A$63 million, is possible using this system to target fungicide application. This system can be applied similarly to other health components to further elevate wheat production in Western Australia.

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The New Zealand Institute for Plant & Food Research Ltd [email protected]

(1)

(2)

Plant & Food Research, Private Bag 92 169, Auckland 1142, New Zealand Plant & Food Research, Private Bag 3230, Hamilton 3240, New Zealand

Crown canker is a serious disease of the purple passion fruit (Passiflora edulis Sims.) in New Zealand often killing more than 80% of new plantings. Outbreaks only occur in winter under cold and wet conditions (May-October), and younger vines (< 18 months) appear the most susceptible to the disease. Characteristic symptoms first develop as purplish spots on the bark in the root crown area and within 50 cm of ground level. As the disease progresses, the spots develop into cankers, which extend resulting in girdling of the trunk and death of the plant. The cankers typically become covered by conspicuous pink/ orange coloured masses of fungal spores. Isolations made from ten affected orchards in Northland (2), Auckland (2) and the Bay of Plenty (6) suggest Fusarium sambucinum Fückel. is the causative pathogen. The fungus was isolated from discoloured phloem and xylem in the trunk and from masses of spores from cankers. It was not recovered from roots nor was any other pathogen (e.g. Phytophthora). A pot trial provided no conclusive answer to the site of infection (entry point into vine). Vines were inoculated by wounding and applying spores of F. sambucinum to the (a) roots, (b) root crown area and (c) trunk (10 vines per treatment plus 10 untreated control vines). Infection was initiated in the vines inoculated in the trunk and crown area but was contained by the plants and did not progress into crown canker. A series of fungicidal and nonchemical trials were undertaken to find control remedies. These included (1) application of prothioconazole and carbendazim to the trunk and larger branches using a spray lance at 3-weekly intervals, (2) raising the temperature of the root crown area and lower trunk by insulating with wood chip mulch and insulation foil, and (3) planting the vines in planter bags in a bark-coir mix to allow increased water drainage. Treatments were replicated in three orchards with 10-20 vines per treatment and untreated vines as controls. No control of the disease was achieved by either fungicide. Although F. sambucinum has optimal infection conditions at low temperatures, an increase in temperature by up to 4.7°C recorded in the root crown area of the insulated vines, did not suppress the disease. Likewise, planting the vines in planter bags did not reduce the incidence of crown canker. Vines resistant to the disease may be the best solution. However, such cultivars need to be developed.


SESSION 4A – DISEASE MANAGEMENT

Enhancing natural disease resistance in Pinus radiata

Evaluation of Trichoderma isolates to suppress Rhizoctonia diseases on potato

Dr Tony Reglinski

Ms Emily Hicks

Tony Reglinski (1), Robert Hill (2), Joe Taylor (1), Mike Spiers (1), Annette Ah Chee(1), Nicholas Cummings (2)

Hicks, E., Bienkowski, D., Braithwaite, M., Falloon, R.E., McLean, K.L. , Stewart, A

The New Zealand Institute for Plant and Food Research Ltd, Ruakura Research centre, Hamilton, New Zealand. (2) Bio-Protection Research Centre, Lincoln University, Christchurch, New Zealand.

Bio-Protection Research Centre, PO Box 85084, Lincoln University, Lincoln 7647, Canterbury, New Zealand

The New Zealand Institute for Plant and Food Research Ltd [email protected]

(1)

New Zealand forest nurseries annually produce approximately 44 million Pinus radiata seedlings, cuttings or plantlets for re-establishment and new areas of forest plantation. Chemical fungicides are routinely applied to manage diseases. However, concerns about their detrimental ecological and environmental effects have led to the withdrawal of some products. The New Zealand forestry industry is supporting research to investigate the potential of biologically based control methods (inducing agents and antagonists) as more sustainable options for pest and disease management. A common criticism of biological control is that it can be highly efficacious in the laboratory or the glasshouse but extremely variable in the field environment. One possible approach to overcome this problem is to combine treatments with complementary modes of action such as the use of microbial antagonists with plant defence activators. We have investigated the use of the plant defence activator methyl jasmonate (MeJA) and Trichoderma spp. for their potential to protect P. radiata seedlings against diplodia dieback caused by Diplodia pinea. Foliar application of MeJA induces a dose-dependent resistance to diplodia which is greatest (c. 60% reduction in dieback, ~0.05) 1-2 weeks after treatment and persists for approximately one month. The induced resistance response is concomitant with an elevation of defence mechanisms and an inhibition of seedling growth. Root application of Trichoderma has been shown to promote seedling growth and/or reduce seedling mortality in commercial forest nursery trials. In glasshouse studies, Trichoderma isolates have been identified which induce systemic resistance to diplodia, resulting in a 20% (~0.05) reduction of dieback compared with the untreated control. Combining a foliar spray of MeJA with Trichoderma root treatment did not have an added effect on dieback control and did not alleviate MeJA-induced growth inhibition. However, there was evidence that the addition of Trichoderma primed the seedling response to MeJA because peroxidase activity was greater in seedlings that were treated with Trichoderma+MeJA than in seedlings treated with MeJA alone, whilst Trichoderma alone did not affect peroxidase. Trials have commenced to screen new Trichoderma/elicitor combinations for potential to control Terminal crook caused by Colletotrichum acutatum f.sp. pinea. Preliminary experiments indicate that foliar applications of salicylic acid or MeJA can result in a reduction in the incidence of Terminal crook in young seedlings. Issues affecting the practical implementation of biologically based control methods for disease control in forest nurseries will be discussed.

Bio-Protection Research Centre [email protected]

Rhizoctonia solani Kühn, is a soil-borne fungal plant pathogen which causes economic losses in potato production worldwide. Symptoms include; lesions (cankers) on the below-ground shoots, stems and stolons, malformed tubers, and formation of sclerotia on the daughter tubers. Rhizoctonia diseases of potato are commonly managed using a combination of cultural and chemical disease control strategies to reduce soil-borne and tuber-borne inoculum. Biological control could have an important role as an additional strategy for Rhizoctonia disease management. Biological control agents, such as formulations of Trichoderma spp., are marketed for many plant pathogens worldwide, however no Trichoderma products are available to manage R. solani in New Zealand. Trichoderma spp. are also reported to be associated with increased crop productivity in numerous crops. In the present research, Trichoderma spp. from New Zealand soils were screened using potato plants, in several greenhouse experiments and one field trial. Fortyseven Trichoderma isolates were screened for Rhizoctonia disease suppression, and 38 were screened for plant growth promotion. Isolates of T. virens, T. atroviride and T. rossicum demonstrated the greatest suppression of R. solani on potato plants; the percentage of diseased stolons was reduced by 41-46% (~0.05), compared with the R. solani-inoculated control. Two isolates, a T. virens and a T. atroviride, also increased (~0.05) average tuber weight, by 210 and 146% respectively, compared with the inoculated control. In plant growth promotion pot trials, three isolates (two isolates of T. harzianum and one Trichoderma sp.) increased (~0.05) number of tubers, total tuber weight and average tuber weight respectively, compared with the untreated control. Six isolates were selected from the disease suppression and growth promotion experiments, and were evaluated in all combinations in a 26 factorial greenhouse experiment. The multi factorial analysis demonstrated that one isolate of T. atroviride showed promise as a biological control agent of Rhizoctonia diseases of potato. Four of the isolate combinations were subsequently tested in a field trial during the 2011/12 season. This demonstrated that two Trichoderma combinations increased (~0.05) potato tuber yield. This research has shown potential for use of New Zealand isolates of Trichoderma to suppress Rhizoctonia diseases of potato.


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SESSION 4B – DISEASE MANAGEMENT

Awheto: initial cultural studies in New Zealand Dr Seona Casonato

Plant and Food Research [email protected] Seona Casonato (1) , Nicola Mauchline (1), Kate Stannard (1), Garry Hill (1) (1)

The New Zealand Institute for Plant & Food Research Ltd, 412 No 1 Road, Te Puke 3182,New Zealand

Introgression breeding– towards the development of nematode resistant sugarcane variety in Australia Dr Shamsul Bhuiyan BSES Limited [email protected]

Shamsul A Bhuiyan(1), Barry J Croft(1), Eunice Wong (1), Phil Jackson(2), Graham R Stirling(3), Mike Cox (4) Biosecurity, BSES Limited, Woodford, Qld, 4514, Australia CSIRO Plant Industry, Townsville, Qld, Australia Biological Crop Protection, Brisbane, Qld, Australia (4) Variety Improvement, BSES Limited, Bundaberg, Qld, Australia (1)

Ophiocordyceps robertsii (Hook.) G.H. Sung, J.M. Sung, HywelJones & Spatafora is an entomopathogen present in some forested areas in New Zealand. It is predominantly found on Lepidopteran larva and specifically associated with the family Hepialidae. In New Zealand the organism is most commonly referred to by the Maori name awheto. Ophiocordyceps is used medicinally in China and Japan and has an extremely high commodity value. Little is known about O. robertsii and its growth patterns. Initial trials have commenced to address these questions. O. robertsii was grown on media optimised for cordyceps growth and contained 1.95% PDA, 1.5% agar and 0.1% yeast extract. Initial temperature and light trials determined that, in culture, O. robertsii grows at its optimum rate in natural daylight hours at a temperature between 17-20ºC. The media used for the growth of O. robertsii (as described above) was further amended with ground hinau leaves (Elaeocarpus dentatus), soil surrounding the awheto, soil not near the awheto, and ground awheto. Initial measurements indicated that O. robertsii grew best on the cordyceps media and the ground awheto media. Least growth was observed on the media containing ground hinau leaves.

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(2) (3)

Root knot (Meloidogyne javanica) and root lesion (Pratylenchus zeae) nematodes are the most important nematode pests of sugarcane in Australia, causing in excess of A$82 million losses to the Australian sugar industry annually. Currently no commercial sugarcane varieties are resistant to these nematodes. A collaborative introgression program with Chinese institutes has used new sources of germplasm, Erianthus arundinaceus and Saccharum spontaneum clones to generate over 100 new families. In 2012, approximately 150 clones from different introgression families have been screened in a glasshouse for resistance to M. javanica and P. zeae. The initial nematode population used for inoculation of test clones (Pi) and final population recovered after 12 weeks (Pf), were used to determine the multiplication factor (MF) =Pf/Pi, which is a measure of the resistance levels of test clones. For both nematodes, the lowest multiplication factors were observed on basic E. arundinaceus (MF = 3 - 7) and S. spontaneum (MF =1.8 - 6) clones, indicating moderate to high levels of resistance. Average levels of resistance tended to decrease with successive backcrosses between the wild species and commercial sugarcane. However, approximately 30% of backcross-three (BC3) populations of E. arundinaceus showed moderate resistance (MF≤10) to root knot and lesion nematodes compared to commercial varieties Q208 (MF 14 42), Q240 (MF 20 - 24) and Q135 (MF 24 - 44). For backcrosstwo (BC2) S. spontaneum populations, 5% and 30% of clones had moderate levels of resistance (MF≤10) to lesion and root knot nematodes, respectively. Individual nematode-resistant clones will be further tested and may prove to be a useful source of resistance to nematodes for commercial production or as parents for further breeding. New introgression clones will also be screened in coming years.


SESSION 4B – DISEASE MANAGEMENT

Managing Ganoderma basal stem rot of oil palm: Innovative approach through endophytic microorganism application

Optimising pruning wound protection for management of eutypa dieback in grapevine

Dr Shamala Sundram

Mr Matthew Ayres

Shamala Sundram(1), Sariah Meon(2), Idris Abu Seman(1), Radziah Othman(2)

Matthew Ayres(1), Trevor Wicks(1), Eileen Scott(2), Mark Sosnowski(1)

Malaysian Palm Oil Board [email protected]

Malaysian Palm Oil Board, P. O. Box 10620, 50720 Kuala Lumpur, Malaysia (2) Agriculture Faculty, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia

South Australian Research and Development Institute [email protected]

(1)

(1)

Basal stem rot of oil palm (Elaeis guineensis Jacq.) caused by Ganoderma spp is the most devastating disease of oil palm in South East Asia. Endophytic microorganisms such as arbuscular mycorrhizal fungi (AMF) and endophytic bacteria (EB) has been previously described as potential biocontrol agents. The potential use of these endophytic microorganisms was investigated through antagonistic assessment against Ganoderma followed by in vitro compatibility between both endophytes, determination of biochemical responses and gene expression profile in pre-inoculated seedlings challenged with G. boninense, and finally field trial via seedling baiting technique. AMF (Glomus intraradices and G. clarum) and EB (Pseudomonas aeruginosa and Burkholderia cepacia) represent the endophytic microorganisms. Symbiotic interaction was observed between AMF species and EB with significant increase of germination and hyphal length of AMF spores. An interesting finding as these EB strains was never reported as potential mycorrhizal helper bacteria (MHB). Antagonistic effect of EB strains was also recorded through radial inhibition while scanning electron micrographs revealed severe morphological deformities such as shrivelling, flattening and shrinking of G. boninense hyphae in the presence EB strains. Production of POX, PPO, chitinase and β-1, 3-glucanase during pre and post infection were enhanced in pre-inoculated seedlings and confirmed by the gene expression analysis. Field evaluation via seedling bait technique recorded reduced disease development. This is the first report of field seedling baiting technique to be successfully implemented in testing microbial pre-inoculation for disease suppression. Pre-inoculation with AMF and P. aeruginosa was most effective in reducing disease severity in oil palm.

(2)

South Australian Research and Development Institute, GPO Box 397, Adelaide, South Australia, 5001 School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, Glen Osmond, South Australia, 5064

Eutypa dieback is a major fungal disease of grapevines worldwide, causing decline and eventual death of vines. Pruning wounds are infected by spores of the fungus Eutypa lata and, once infected, the only method of control is via drastic remedial surgery. In Australia, only two products are registered as pruning wound protectants, and these must be applied by hand, which is not economically viable in most commercial vineyards. In order to optimise control of eutypa dieback, appropriate rates of fungicides need to be determined and efficient methods of spray application developed. Field trials were conducted in vineyards for two seasons to evaluate a range of fungicides and alternative products for efficacy in protecting pruning wounds from infection by E. lata. Vines were treated and inoculated with 1000 ascospores/wound following pruning in winter and then canes were removed the following winter for isolation in the laboratory. Recovery of E. lata from inoculated controls in the two seasons was 92 and 55%, respectively, and natural infection was detected in 8 and 13% of non-inoculated wounds. The fungicides tebuconazole, pyrimethanil, pyraclostrobin and fluazinam, representing four chemical activity groups, provided up to 88, 77, 71 and 58% disease control, respectively. Detached cane assays were also established in the greenhouse to evaluate the fungicides at decreasing inoculum doses from 1000 to 200 spores/wound, confirming the efficacy of the above fungicides. Of the alternative treatments evaluated in the field, garlic and lactoferrin provided 52 and 65% disease control, respectively. To develop efficient methods of applying pruning wound treatments, a range of different types of commercial sprayers was evaluated in three vineyards for two seasons. Spray coverage was assessed using water-sensitive papers placed throughout the vines. There was a positive correlation (R2=0.5) between spray coverage and disease control. The most effective sprayers were those that best targeted the vine cordons. Recycle and purpose-built sprayers achieved up to 93% disease control, equivalent to that achieved by handpainting of wounds. Most commercial sprayers are designed to spray foliage of vines and therefore require nozzle adjustment to target the pruning wound zone and high water volumes (>600 L/ha) to achieve maximum wound coverage. The outcome of this research provides new options for grape-growers to manage eutypa dieback and contributes to the long-term sustainability of the Australian wine industry.


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SESSION 4C – DISEASE MANAGEMENT

Containment and eradication of Phytophthora cinnamomi in natural ecosystems

Impact of fungicide resistance in Venturia inaequalis on control of apple scab in New Zealand

Prof Giles Hardy

Dr Robert Beresford

William Dunstan(1), Trudy Paap(1), Michael Crone(1), Christopher Dunne(2), Treena Burgess(1), Colin Crane(2), Renee Hartley(2), Giles Hardy(1)

Rob Beresford(1), Peter Wright(2), Suvi Viljanen-Rollinson(3), Peter Wood(4), Ngaire Larsen(1)

Centre for Phytophthora Science and Management, School of Veterinary and Life Sciences, Murdoch University, Murdoch, Western Australia, 6150 (2) Science Division, Department of Parks and Wildlife, Locked Bag 104, Bentley Delivery Centre, Western Australia 6983

(1)

Murdoch University [email protected]


(1)

The exotic soil-borne plant pathogen Phytophthora cinnamomi is recognized as one of 15 ‘Key Threatening Processes’ to Australia’s biodiversity. In the south-west of Western Australia an estimated 41% of the 5710 native described plant species are susceptible and over one million hectares of native vegetation is infested. Therefore, robust methods that can effectively contain and eradicate the pathogen are paramount for the protection of remaining uninfested areas. Since P. cinnamomi is a poor saprotroph and that it can survive indefinitely in asymptomatic annual and herbaceous perennial species, we describe two methods that can effectively be used to eradicate and contain P. cinnamomi from spot infestations. Firstly, we applied herbicides to kill plants followed by the application of the fumigants Metham and Dazomet to depth to kill the pathogen. Secondly, we used herbicides to kill all plants and ensured that no recruitment from soil seedbanks occurred over a period of two years, with no other treatments. With regular baiting of the soils we were able to show no recoveries of the pathogen up to 36 months after treatments. The methods can be applied to spot infestations in a wide range of environments to ensure large areas do not become infested through autonomous or anthropogenic spread. We are now using the herbicide approach to ensure no living hosts occur at any time to provide the pathogen with a living substrate in restored minesites on rehabilitated haul roads, and topsoil and overburden stockpiles. This method will potentially allow us to return within 24-36 months of treatment large areas of jarrah forest that were infested by the pathogen prior to mining to a pathogen-free status post mining. A detailed description of the approaches together with the recommended containment, monitoring, sampling and hygiene procedures will be discussed. There is a need to incorporate this containment and eradication methodology into comprehensive management plans for high priority landscapes.

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The New Zealand Institute for Plant & Food Research Ltd, Private Bag 92169, Auckland 1142, New Zealand The New Zealand Institute for Plant & Food Research Ltd Cronin Road, RD1 Pukekohe, New Zealand (3) The New Zealand Institute for Plant & Food Research Ltd Private Bag 4704, Christchurch, New Zealand (4) The New Zealand Institute for Plant & Food Research Ltd, Private Bag 1401, Hastings 4157, New Zealand (2)

Apple production in New Zealand, as elsewhere, relies on fungicides to control scab (black spot). Some fungicides are at risk from resistance, including the groups: demethylation inhibitor (DMI), guanidine derivative (dodine), quinone outside inhibitor (QoI or strobilurin) and anilinopyrimidine (AP). Fungicide resistance reduces disease control, which decreases revenue, increases orchard and post-harvest handling costs and threatens market access by increasing risks of chemical residues and phytosanitary failures. Of available fungicides not at risk from resistance, dithiocarbamates interfere with integrated mite control, and others increase risk of fruit russet. In spring 2009, widespread scab control failure in Nelson was initially attributed to high disease carry-over, unexpectedly early bud break and difficult spraying conditions. In conjunction with Pipfruit New Zealand Inc. the national resistance status of V. inaequalis to dodine, DMIs, QoIs and APs has been investigated since 2010. Fifty orchards were surveyed in Hawke’s Bay (27), Nelson (12), Otago (6) and Waikato (5), providing about 1000 V. inaequalis isolates. Sensitivity to two DMIs (myclobutanil and penconazole) and to dodine was tested using agar-based mycelial growth assays. The degree of resistance associated with loss of disease control was determined for each fungicide group by a plant bioassay, using inoculated potted apple trees. QoIs were tested by DNA-based detection of the G143A mutation in the cytochrome b gene. Isolates carrying the mutation were resistant to trifloxystrobin in both agar and plant assays. An agar-based assay for AP fungicides (pyrimethanil and cyprodinil) was also developed and validated using plant bioassays. The national survey showed resistance to myclobutanil, sufficient to compromise disease control, occurred in all regions. Sensitivity to myclobutanil and penconazole was about 10 times lower than overseas baseline sensitivities. Plant bioassays showed the DMIs flusilazole and difenoconazole were less affected by resistance than myclobutanil, penconazole and fenbuconazole. Sensitivity to dodine had increased since the 1990s, apparently the result of more rigorous dodine resistance management guidelines since 2004. For QoIs, the G143A gene mutation frequency was high enough to compromise disease control in 59% of orchards, nationally. AP sensitivity testing is incomplete, but initial results suggest resistance is widespread in Nelson. It is now considered that the 2009 scab outbreak arose because of resistance to at least two fungicide groups, combined with a challenging season for scab control. Information from this study is being used to develop new fungicide resistance management guidelines for the New Zealand apple industry.



Heat and chemical treatments to reduce systemic infection of tissue culture derived boysenberry plants (Rubus spp.) by the downy mildew pathogen Peronospora sparsa Ms Anusara Herath Mudiyanselage

Evaluation of PCR methods for detection and identification of Xylella fastidiosa in Coffea sp. plant Ms Françoise Poliakoff Anses - Plant Health Laboratory Franç[email protected]

Ecology Department, Lincoln University [email protected]

Bruno Legendre (1), Stelly Mississipi (2), Valérie Olivier (1), Emmanuelle Morel (2), Dominique Crouzillat (2), Marie-Agnès Jaques (3), Françoise Poliakoff (1),

Anusara Herath Mudiyanselage(1), Marlene Jaspers(1), Hayley Ridgway(1), Monika Walter(2), Geoff Langford(3), Eirian Jones(1),

(1)

Faculty of Agriculture & Life Sciences, Lincoln University, Lincoln 7647, Christchurch, New Zealand (2) Plant & Food Research Nelson, Old Mill RD, RD3, Motueka, 7198, New Zealand (3) Berryworld Ltd, Tai Tapu, RD 2, Christchurch, New Zealand (1)

Downy mildew, caused by the pathogen Peronospora sparsa, is a major disease of boysenberry in New Zealand, which, in recent years has resulted in yield losses of 50-100% mainly due to development of dryberries which are prematurely reddened, shrivelled, hardened fruit. Systemic infection of the plants produces characteristic purple angular leaf lesions along the veins. The use of systemically infected plants for propagation has resulted in young plants being infected. To limit infection of new boysenberry canes prior to their use in tissue culture, two treatments, heat (34°C) and heat + pesticide sprays (mancozeb and phosphorous acid), were applied. The systemically infected boysenberry plants (cv. Mapua) were grown in a greenhouse for 4 weeks, during which the plants for the pesticide treatments were sprayed after 2 and 4 weeks prior to placing at 34°C, with the heat only plants. Control plants were grown in the greenhouse for the duration. After 4 weeks growth at 34°C, cane tips were used to initiate tissue culture with 1-2 cm, single-bud stem cuttings as the explant material. Survival of the tissue culture plants from heat only, heat + pesticide and control treatments was 41, 48 and 74%, respectively after 6 weeks. The plants from the above treatments were potted up and grown in the shadehouse under conditions conducive to expression of systemic symptoms for 3 months. Characteristic P. sparsa symptoms were observed in 13, 17 and 100% of the heat only, heat + pesticide and control treatments, respectively. A nested PCR method was used to verify infection status of the plants. An initial test indicated that, although variable, the best detection rate was achieved using leaf tissue. Leaf samples from the 127 canes produced on the plants showed that 1.6% were infected and all of these were from the heat only treatment. Plants diagnosed as free of the pathogen will be used for propagation. Random sampling will be conducted during growth of the propagated plants to ensure that they are pathogen free as the possibility remains that systemic infection was present but below the detection threshold of the nested PCR. The results indicated that treatment with heat either alone, or in combination with mancozeb and phosphorous acid, reduced the level of systemic infection in the plant material. This method, together with PCR detection to confirm uninfected status, provides a valuable tool for the production of boysenberry planting material free of P. sparsa infection.

French Agency for Food, environmental and occupational health and safety - Anses - Plant Health Laboratory, Angers, 7 rue Jean Dixméras 49044 Angers cedex 01 - France (2) Nestlé Research Center, 101, Av. Gustave Eiffel Notre Dame d’Oé B.P.49716 - 37097 Tours CEDEX 2 - France (3) INRA – EMERSYS - UMR1345 Institut de Recherches en Horticulture et Semences - Centre Angers-Nantes, 42 rue Georges Morel - BP 60057 - 49071 Beaucouzé cedex – France.

Xylella fastidiosa (Xf) is a bacterium listed in the European Directive 2000/29/EC absent in this territory. This xylem-limited bacterium is present in the Americas and recently emerges in Taiwan. As it can infect nearly 250 hosts including some of high economic importance for France (Vitis vinifera, Prunus spp., Citrus sinensis, Medicago sativa, ornamental plants and forestry trees, ...), woody fruit plant coming from areas suspected to be infected are subject to a stay in quarantine facilities. Nevertherless, in 2012, Plant Health Laboratory detected in France Xylella fastidiosa from symptoms on imported Coffea sp. plants. This finding is considered as an interception (European Plant Protection Organization (EPPO) - RS 2012/165). Detection tools as sensitive and specific as possible are necessary for quarantine laboratories to ensure release of healthy plant material. To reach this goal, the methods of detection using regular PCR (Minsavage et al. 1994) and realtime PCR (Harper et al. 2010) were evaluated on coffee plants for their performance in terms of sensitivity, specificity, detection threshold and reproducibility. A protocol for detection of Xylella fastidiosa is proposed to improve the control of Coffea sp. plant material.


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Application of the PBcast model for timing fungicide sprays to control Phytophthora blight of pepper

Protection of apple budding wounds from European canker Dr Reiny Scheper


Dr Eunwoo Park

Seoul National University [email protected]

Reiny Scheper, Owen Stevenson

Mun Il Ahn(1), Ki Seok Do(2), Kyeong Hee Lee(3), Wee Soo Kang(1), Eun Woo Park(2), Epinet Research Institute, Epinet Co. Ltd., Anyang, 431-810, Korea Department of Agricultural Biotechnology, Seoul National University, Seoul, 151-921, Korea (3) Environment-friendly Agricultural Research Division, Chungcheongbukdo Agricultural Research and Extension Services, Cheongwon, 363-883, Korea

The New Zealand Institute for Plant & Food Research Limited, Private Bag 1401, Havelock North, New Zealand

(1) (2)

Phytophthora blight of pepper which is caused by Phytophthora capcisi often results in serious damage to pepper production due to failure of disease control at the early stage of disease development in the field. Therefore, it is important to determine when fungicide sprays need to be initiated after overwintering to control the disease effectively. This study was conducted to evaluate the effectiveness of fungicide sprays based on the forecast by PBcast, an infection risk model for Phytophthora blight. The PBcast uses weather (daily mean temperature, relative humidity, and rainfall) and soil texture data to estimate daily infection risk of the disease. Treatments included (1) routine sprays at 7-day intervals; (2) sprays when the infection risk estimated by PBcast reached 200 (IR=200); (3) sprays when the infection risk estimated by PBcast reached 224 (IR=224): and (4) no sprays. The field plot was arranged in the randomized complete block design with four replications. The experiment was conducted at the pepper field of the Chungcheongbukdo Agricultural Research and Extension Services, Korea in 2012. Disease incidence was assess weekly in terms of the percentage of diseased plants for individual plots. Throughout the growing season, the infection risk estimated by PBcast has reached higher than 200 twice, but less than 224. Consequently, the plots for IR=200 have received fungicide sprays twice, and no sprays were applied to the plots for IR=224. The routine spray plots were sprayed 17 times at 7-day intervals. The PBcast and the routine spray programs resulted in disease incidence of of 2.5% and 1.5%, respectively, whereas the disease incidence of no spray plots was 47.5%. Considering that pepper growers in Korea commonly apply 8-9 sprays of fungicides to control the disease in a growing season, the PBcast forecast may help pepper growers reduce fungicide sprays significantly without losing the disease control efficacy.

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European canker, caused by the fungus Neonectria ditissima, was shown to infect apple nursery trees in a UK study. Therefore, protection of budding wounds may be important for canker management. Approximately 1800 ‘EMLA 9’ rootstocks were planted in Motueka, New Zealand, in October 2008 and budded with ‘Royal Gala’ in March 2009. Ten treatments at budding included different budding tapes and methods (Buddy tape, plastic pre-cut budding strips and Flexiband type C when chip-budded, and Flexiband A rubber budding strips and Okulette O30 when T-budded), and three fungicidal treatments that were applied to chip-budded stocks taped with Buddy tape. Treatments included slaked lime (3.2% calcium hydroxide), 0.15% Pristine® (0.0192% pyraclostrobin and 0.0378% bocsalid) in 50% water-based acrylic paint, and a mixture of 1% tebuconazole and 2.5% carbendazim in 50% water-based acrylic paint (4% Folicur® WG and 5% Headland Addstem, respectively). The buds tied with Okulettes were on the same rootstock as the buds tied with Flexiband C, but 20 cm above these buds, and were removed 5 months after budding. All buds, except the controls, were inoculated with conidia of N. ditissima (2x105 conidia/ ml) after the treatment. The positive controls were chip-budded, inoculated and then taped with Buddy tape, and the negative controls were chip-budded, taped with Buddy tape and treated with 0.005% Tween® 20. Five months after budding, significantly more buds and rootstocks among the positive controls (100%) and buds that were tied with Flexiband A rubber strips after T-budding (99%) displayed canker symptoms than in all other treatments (P